Wednesday, July 26, 2017

Time to Include More Hardware Devices in Teaching Computer Science?

Lately I have been thinking hard about including small programmable devices in my programming courses. Talking about his on Twitter brought me both encouragement and some discouragement. The discouragement challenged me to think harder about why I wanted to use these devices. Pat of that challenge was a link to a paper by Monica M. McGill called "Learning to Program with Personal Robots: Influences on Student Motivation" IF you don't have access to the ACM Library and really want to read it let me know.

That research work focused on the use of robots as a motivational tool. The results were not that encouraging. A lot of the complexities of using robots, fickle hardware, batteries running out, software that is not quite there yet, and other logistical items probably apply to small programmable devices of other sorts. The robots didn't seem to be as motivating as the authors, and many supporters, would have hoped. Students didn't see the robots as relevant to their lives and interests. SO are the robots worth it? It's a fair question. Are my little devices going to be different? If so, different in what way? So many questions.

My thinking is that I need to look at more things to determine how or if I should proceed. Addressing some of the logistical issues is of course important. The "why" of going through that is the bigger question. Here I look to relevancy. This is were I see some potential differences from robots. The challenge becomes more than creating projects that are meaningful and motivating for the students. I have to have and communicate a reason why students should be learning g about these devices. Something beyond the project of the hour.

We're really moving, some would say have moved already, into an era with we are seeing smart devices everywhere. Many of these devices are tied in with "the cloud." Are we preparing students to deal with that reality with software only computer science education? I'm concerned that we are not.

I asked the questions "Wondering if it is time to more software people to learn more hardware? Do we need to be teaching more of this stuff as well?"and received  a lot of positive responses from both educators and industry friends. The support did not come without more questions (I have smart friends) such as where in the K-16 CS curriculum should it come and what sort of things should be included? We are really still figuring out this whole CS for All thing. (BTW Mark Guzdial's CS Curricula, Standards, and Frameworks will Need to Change for more on this.) In a way, this needing to figure things out makes me want to try more. Someone has to do it. Trying things on a small scale seems to me to be worth the effort. I want students to think about hardware and how it is part of a complete system. I want them to see that they can combine hardware and software in new ways to create new things.

Will this be more motivating? I don't know. Will it help them learn programming faster or better? Again I don't know and the research suggests not in a big way. On the other hand it seems likely to teach themselves some things they would not learn at all without the involvement of hardware.

I haven't yet seen much research out of the UK on the impact of the BBC Micro:bit. They didn't really have a full year to work with it though so it is early. People using it still seem enthusiastic  about it. People are starting to develop more software and curriculum around the Micro:bit, Arduino , Raspberry Pi, AdaFruit Circuit Playground and other similar devices so I don't feel alone. Well not completely at least. And I am going into it with modest expectations.

I'd like to hear from others who are asking these questions as well. Do you use these small devices? If so, why? If not, why not?

Sunday, July 23, 2017

Is Computer Science Education Facing a Bursting Bubble?

The other day Audrey Watters, one of my favorite contrarians, posted  Why Are Coding Bootcamps Going Out of Business? which focused on the failure of some coding bootcamps and the consolidation of others. Today I read A Tech Bubble Killed Computer Science Once, Can It Do So Again? also posted in the last few days. Articles like these make on think about the future of CS education. Well I think about that a lot anyway but mostly I travel in upbeat circles. CS education is seeing growing interest and is being taught to more students. All good right?

Both of these articles focus on CS education as a way to get jobs in software development. While that is probably a good reason to study CS it is not the only one. Of course we have seen lowering demand for CS professionals decrease interest in studying CS drop in the past. SO it is something we do have to look at and think about.

Part of the problem here is getting a clear view of the demand for CS professionals. Many companies say there is a shortage of skilled developers. The contrarian view is that there is a shortage of people willing to do the job for the money being offered. Those people see the calls for more H1B visas as a way to keep salaries low more than as a way to fill a real shortage. I suspect the way the Trump administration looks at foreign workers (see the H2B visa shortage this summer) may give us a chance to find out. On the other hand some people predict that tech companies are headed for a bubble burst so there is that as well.

If tech companies do falter that may indeed cause a drop in interest in CS education. I’m not quite ready to predict an eminent bubble burst there though. It really feels to me like a lot of things are moving forward very strongly and very widely across industries for that to happen soon. We’ll have to keep an eye on what this means for jobs though. While it looks like starting salaries for recent university graduates are up slightly (Salaries for 2017 College Grads Hit All-Time High) tech like many other industries has this tendency to hire young and squeeze out older more expensive workers. I hear lots of stories of how hard it is for experienced professionals in their 40s and 50, let alone 60s, to get jobs in tech.

Personally I still maintain that learning CS is important for people in all lines of work and that becoming a professional software developer is not the only or even the best reason to teach CS to everyone. Even if there is a drop in people majoring in the field if there is an increase of people learning some CS we’ll be better off. The hard part is convincing all these other people that the reasons we teach all HS students Physics and Biology are just as valid, if not more so, for computer science. We need to go beyond the vocational idea of CS education. If we can do that we can continue to see CS education grow to the benefit of us all.

Friday, July 21, 2017

Five Must Read Blogs for Computer Science Teachers

I maintain a computer science education blog roll with as many good blogs for computer science teachers as I can find. It's a good like for the most part. Some of the blogs listed are seldom updated though. And some are really more general purpose education or not as focused on CS education. (Doug Peterson's blog is an example but I never miss it.) So I decided to write about the five best in my humble opinion. Just to get people started. Other than the first, these are in no particular order. I always read these blogs.

If you only read on blog it should probably be Mark Guzdial's Computing Education Blog  Mark is probably doing more research in how to teach computer science right than anyone else I know.  He talks about the work they are doing at Georgia Tech both in terms of teaching new and different courses there as well as the Georgia Computes! program that is helping to develop more CS education at the HS level in Georgia. I wish I wrote half as well as Mark. Whether if be his commentary on the various articles he finds or information about his own work or discussion of  things his graduate students are doing what you will find here are well thought out, well written and informative posts. His are the first posts I read most days.

For some often contrary opinions but always interesting reads try Mike Zamansky Mike used to run the computer science program at Stuyvesant High School in New York City (a top public magnet school).  These days he is working on the honors program at Hunter College. He has strong opinions and a long background in teaching CS to back them up. If you want someone who doesn't just take ideas at face value Mike is the man to read.

The small school perspective is a highlight on posts by Garth's CS Teacher Blog  Garth Flint is a teacher at a private Catholic school in western Montana. Garth always gives me things to think about. He writes about curriculum (He's always trying new things), teaching, and even some system management. In many small schools the CS teacher is also tech support. I love his writing style as well.

Doug Bergman is the award winning head of Computer Science at Porter-Gaud School in Charleston, SC. Doug is very innovative and a huge proponent of project based learning. He is also great at getting grant money to buy new hardware for teaching CS. Robots, Kinects, and even HoloLens devices show up in his lab (and blog posts) as he has students work on very interesting projects. Doug gets excited and it shows.

I recommend my blog as well. I think to think I write with a teacher voice but my background in industry over the years gives me a different perspective. Plus I link to good stuff from the (possibly too many)  blogs I follow as well other things I find on social media. If you don't care about my ideas you may still find value in the stuff I share. Sharing good ideas from others is my passion.

Thursday, July 20, 2017

Algorithms, Bias, and Beautiful Women

I've been keeping my eyes open for things to discuss with students this fall, especially in Advanced Placement Computer Science Principles. This week bias in algorithms kept crossing my path. It was even a topic for the #EthicalCS Twitter chat this week. It's a real problem if we really want software to meet the needs of everyone. And really to keep people safe.

I've got a couple of good examples to share. One is attempts to scientifically determine what beautiful women look like. Personally I think that is a silly goal as beautiful is in the eye of the beholder but it sells magazines I guess. Take a look at this story. The 10 Most Beautiful Women in the World, According to Science. All of the women are white. Do we really believe that beauty is limited to white women or is there perhaps a bias involved? I would suggest the latter.

While that is sort of trivial in the scheme of things some biases in algorithms have a lot more risk. Take this story A white mask worked better': why algorithms are not colour blind about the discovery that some facial recognition doesn't recognize Black faces. More information at this TED Talk Joy Buolamwini - How I'm Fighting Bias in Algorithms. Imagine the possibilities. Police and other authorities use this sort of software and this suggests the possibilities for miss identification are frightening.

Take a look at this story as well Samsung adds and swiftly removes sexist Bixby descriptor tags Not so much an algorithm bias is a software inclusion of biased opinions. How did they miss that? I wonder how many women were in on that decision?

Biases are pretty much unavoidable. As one professor Tweeted me "Most biases are inherent/unavoidable part of cognition. See books by D. Kahneman, R. Thaler, or D. Arielly." If anything this agues for more diversity on software teams. Different biases may, one hopes, help to balance things out in algorithms and software in general. I think though that as educators it is the job of computer science teachers to discuss this issue with students. They need to be aware of the issue if they are to have any chance to moderate the effects.

Wednesday, July 19, 2017

GP–A General Purpose Block Programming Language

GPLogo260I added GP to my list of block programming languages this morning. Mark Guzdial announced on his blog that it was available in Beta (The General Purpose Blocks Programming Language, GP, is now in beta)

According to the website “GP is a free, general-purpose blocks programming language (similar to MIT's Scratch) that is powerful yet easy to learn. It runs on most platforms, including laptops, Chromebooks, tablets, and web browsers.”

This one looks particularly interesting because the GP stands for General Purpose. What does that mean? I think it means more sorts of apps can be developed with it than the more domain specific block languages we have seen so much of.

Since I am not a fan of web apps, that it is available as an executable for a wide variety of platforms (Windows, Raspberry Pi, Mac, and Linux) I’m happy. Available as a web app as well for you Chromebook people!

The development team includes some pretty impressive people who have experience teaching with it. And they have some teaching resources available already because it has been used for teaching. This one seems really worth a deeper dive.

Monday, July 17, 2017

Teach Me How To Teach

Garth Flint hits it out of the part with It is not about coding

Key issue?

"Although both camps were for teachers neither dealt with any pedagogy on how to teach coding or programming. Both stressed syntax and how to read the curriculum they had designed. It was implied in both camps that although pedagogy was important it was something that would somehow be easier that coding and syntax."

This may be the biggest problem with professional development for computer science teachers - we are taught what to teach but not enough of how to do the teaching.

Saturday, July 15, 2017

CSTA 2017–Some Thoughts

Normally I write several blog posts during a CSTA Annual Conference. Not this year. Why? Too much going on! The sessions I attended were very good and my time not at sessions was never boring. Lots of great conversations connecting with new friends and regular attendees. And the exhibits were worth the time as well.
Let me start with the exhibits. I know that there are people with several different opinions about exhibits at conferences but I love them. This year there were over 40 exhibits and they were all relevant to attendees. What were my highlights? Well there was Rolls Royce showing off virtual reality technology that they use in manufacturing and development. They are a technology company make no mistake about it. They need our students.
WP_20170709_11_15_40_ProMaking things was a big topic in the exhibit hall as well. Several people were showing off things to make/create in CS classes. 3D printing, robots, and programmable gadgets. I think physical computing is a coming thing. Microsoft was showing some really cool projects using the Micro:Bit and AdaFruit Circuit playground. Much of these were also at ISTE BTW. They have a web site called that lets students program several devices and Minecraft it
There were several exhibits showing robots with Wonder Workshop (makers of Dot anWP_20170709_14_40_28_Prod Dash) having the largest exhibit. There was a session on the legal ramifications of using drones in education as well.
There were very few sessions on using robots and programmable small devices though. Maybe that will change in the future as there seems to be a lot of interest in all of these things especially in K-8 CS education.
Cyber Security was another big topic at CSTA this year. Lots of people are looking into how that fits into the curriculum. Closely related was a session on ethics which has spawned conversations continuing over the summer on Twitter with the #EthicalCS twitter chat (See Ethics and Computer Science Education )
Social media was a big topic with a lot of people tweeting at the conference and a Birds of a Feature that included a short mini Twitter chat. I did tweet a good bit myself. The conference hashtag was #CSTA2017 and you can look for people’s tweets to see what others were interested in.
Conversations for me were wide ranging. Talks about these cool new devices. Chats about the growth of CS for all and what that means. How we teach different things. What different things. I talked to a number of people about AP CS Principles. Most of us agree it can be a really good course that is rigorous and interesting for both students and teachers. So many ways to teach it though!
A few other observations. I didn’t see as much interest or discussion of mobile phone development. Yes, people are using App Inventor more (or so it appears to me) but they are not as focused on phones. I didn’t hear any iPhone talk. That I didn’t hear something doesn’t mean it wasn’t talked about of course but I do hear a lot.
There was more talk about AP CS Principles than AP CS A. Maybe all the APCS A people feel more established in that course but of a lot of us are still working our way though Principles.
Interest in CS is sure growing. That we had 650+ people suggests that alone. And industry is being supportive with something like 150 people getting funding help from Infosys Foundation, Google, and Rolls Royce to attend. That’s all good. It feels like there were more K-8 teachers this year as well. That is a fast growing area in CS education.
All in all I think I picked the Computer Science Education Things I’m Watching in 2017 back in January. Movement on all fronts. We’ll see what happens in September and the new school year but I think the CSTA Conference is still a leading edge professional development experience for CS educators.
Were you at CSTA? There was much to much for any one person to see it all. What were the things that moved or interested you there?

Friday, July 14, 2017

Ethics and Computer Science Education

Are ethics and the effects of computer science a reason to teach CS to everyone? Increasingly we are seeing all sort of impacts on daily life because of computing. Some are unintended but others are intended and often some of these impacts are not good. What is going on? Basically I think two things. One is that people are not going beyond asking if something can be done to should it be done. The other is just plain unethical behavior done for profit. Perhaps education in ethical thinking can help. It is at least something we should try.

Computing and its effects are still relatively new. We’re doing things today with computers that were the stuff of science fiction not very long ago. Smart phones, GPS navigation, self-driving cars (I heard about self driving boats – big ones – at CSTA this week) and much more. Schools are teaching students how to make these things possible but are we teaching enough about how to weigh the consequences? Not always. But we should.

Teaching good behavior on the Internet and in social media is becoming very common. In fact in some places it is required to be taught. That’s great as far as it goes but computing is so much more than that.

The CS 2013 curriculum for undergraduate includes ethics and professional behavior. But what are we doing in K12? Are ethics part of the discussion in K12 standards? It is in the CS K12 Framework. Still it seems to be on the backburner for many teachers. Why? Well full curriculum for starters. There is not much room for it in the APCS A curriculum. There is in the AP CS Principles curriculum and hopefully there will be some good educational discussions in those classes.

Really though it shouldn’t be a separate topic in my opinion. Ethical behavior is something that we should bake into the curriculum in various contexts. We need students to be thinking about ethics from the very start. I argue that students need to learn to think about if something should be done as they learn how to do it. Take big data for example. Data analysis is a powerful and wonderful tool. It can be used to solve all sorts of problems from medical research to how to get around the neighborhood. But it can also be used in negative ways. Can you imagine what the  Nazis could have done with modern databases? Think on that for a while and realize that there are bad actors in governments in the world today.

Computers can be used to make car engines cleaner and more efficient. They can also be used, as we saw with Volkswagen, to cheat on emissions tests. Did the engineers who wrote that cheat code think about the ethical implications? We’ll probably never know but our students should be taught to think about it.

Some may argue that ethics belongs in a separate course or that CS teachers should leave that teaching to others but I think the special context of CS and in fact the special power that CS knowledge gives requires we, CS teachers, include it in out curriculum. More than that I think that everyone, not just the people who will be CS professionals, needs to understand how to think about ethical computing. Can we really expect business or political leaders to think about ethical use of computers if they don’t have training in the mix? I don’t think so.

The ethics of using computers, how and why they are used and what they can do, is increasingly an important life skill. Ethical computing is another reason we should teach CS for all.

BTW The other day there was a twitter chat about ethics and computer science education (Check the #EthicalCS twitter tag). Saber Khan is organizing them on Wednesday's during the summer (8pm Eastern time) and this was the first. It was an interesting conversation and brought a lot of ideas to light for me. I recommend joining in over the summer.

Thursday, July 06, 2017

Computer Science Teacher or Teacher of Computer Science

In some respects we have an identity problem in computer science education. Some of us think of ourselves as computer science teachers. Generally that means we identify as teaching computer science first. Maybe that is all we teach. Other times it is not the only thing we teach but what we want to teach the most. Either way “computer science teacher” is how we self identify.

Other people see themselves as teachers who also teach some computer science. Some of these teachers see themselves as math teachers, science teachers, gym teachers, or art teachers who also teach some computer science. Others are K-6 or middle school teachers who teach several things or “everything” and computer science is just part of what they do. But many of these teachers feel like they are not in the same category as “real computer science teachers.”

This really shouldn’t be a problem as we all have computer science in common but sometimes it can be. It’s a problem when teachers who teach some computer science think that professional development for computer science teachers isn’t for them. It is though! When I look around the CSTA Annual Conference (which starts in a couple of days) I see all kinds of people who teach computer science and there is something for all of them there. No one asks if people teach something else at a CS PD event unless it is casual conversation or if they want to talk about cross curricula teaching. Many members of the Computer Science Teachers Association have membership in other subject matter associations of teachers and that is great!

I guess it can be a problem if someone really doesn’t want to teach CS and want to be purely some other sort of teacher. As much as I love CS and teaching CS I understand that some people have other priorities. There is only so much time in a teacher’s life for professional development.

Teachers of CS who want to learn more CS  shouldn’t hesitate to jump into things with people they see as computer science (specialist) teachers. As we in our society work to bring computer science to more and more (hopefully all) students there are going to be many more teachers who teach computer science along with other subjects. I hope we can mix CS with more subjects as well. It will make everything more interesting and relevant to teachers and students alike.

So computer science teacher or teacher of computer science – however you see yourself join CSTA, come to chapter meetings, come to our annual conference and know that we’re all in this together.

Wednesday, July 05, 2017

Twitter Chat - teaching computer science away from the computer #InfyEdChat

I'm going to host a twitter chat on Monday, July 10, 5PM PT / 8PM ET. Join me to talk about teaching computer science away from the computer. Bring your ideas and pick up more. Follow #InfyEdChat to take part.
#InfyEdChat (49)[483]

I think most of us are looking for ideas for helping students get the concepts and doing so away from the computer can be more comfortable for make. So jump in with what works to you. See you in Twitter on Monday!

Friday, June 30, 2017

Professional Development for the Advanced CS Teacher Teaching Advanced Students

This is sort of a riff from yesterday’s post about what to teach students who are beyond the normal Advanced Placement CS level or perhaps looking to something advanced in place of the AP course. Most professional development for computer science educators is for teachers who are beginners at teaching CS or who are teaching beginners at learning CS. That’s wonderful as far as it goes but as we move more and more CS down to the younger and younger grades there has to be more. What is that more?

Honestly I am not sure. Of course I have some ideas for topics and I have blogged about them. But are they the right ones and do I, or other teachers, know enough to teach them? OK some of them I think I could handle. I’ve been around the block a few times but there are a lot of teachers who are going to be facing students who know as much as they do very soon. Let’s face it some teachers are facing that already. IF they are not now they will be soon.

We don’t have a good handle of the “what comes next” because it hasn’t often bee an issue. But it would be a good thing if some of  those teachers who teach advanced students already (I’m talking about a large number of people at career/technical schools BTW) would share what they have learned with the rest of us. As I mentioned earlier (After ISTE–More Questions Than Answers ) this topic has come up in the past but we’ve never really addressed it as a community.

I think it is time we put some effort into this situation. What are your thoughts?

Thursday, June 29, 2017

Finished Advanced Placement Computer Science–Now what?

This question is now more complicated since we have two AP CS exams again. Does CS A follow CS P? Should it be one or the other but not both? But let’s put that aside for the moment. Suppose a student takes one of the AP CS courses as a junior (or younger – it happens) where do you go from there?

This may seem related to How Many Times Can You Teach Loops? but it’s not really. We’ll assume that these students have some solid understanding of computer science and programming. Not undergraduate major level but really solid for a high school student. What do you do with them if they want more? And many will want more!

There are a number of options as I see it. One is that you could have a domain specific course. Perhaps network programming. Or web backend programming? Maybe something like a cryptography course? (OK that one I would like to take.) Or go a bit more Information Technology with a system management course. Perhaps network security? Actually you could probably look at the average college catalog and get even more suggestions. All of them are good and interesting. I’ve been thinking along a different line though.

How about a major project course were each student or group of two to four students take on some major programming effort? I’m thinking they should have a customer. Perhaps an app for the school or for a local non profit. That’s the ideal perhaps. But maybe it would ok if they thought about some real tour de force that required them to learn a lot of new things. Maybe even learn some hardware.

What I’d really like to see is a self directed research sort of project. It would take motivated students and a teacher willing to let things get messy. Grading would be a challenge especially if one has to give regular grades to keep administration happy. I’m not really sure how it would work but I’ll bet some students would learn an awful lot.

Wednesday, June 28, 2017

How Many Times Can You Teach Loops?

Suppose you have students learning computer science from first grade to high school. How many times can you teach loops? Maybe you start with blocks using Scratch or Alice and they learn counter loops and perhaps loop forever. Do you teach with that language a couple of years? Maybe. Do you reteach loops for each of t hose years?  Next you switch to a text based language. Now you teach for loops (by some name or other) using words. Maybe you add in while loops. Next year maybe you add in loop until. At some point you add in For Each.Have you taught each of those several years running? Are your students bored yet?

We’re looking at K-12 Computer Science Standards and there is a great K-12 CS Framework. But what exactly do we teach each year? Now perhaps we don’t teach CS every year. Perhaps we decide on one semester in each grade band (defined differently for your situation) where we teach Computer Science. Great now we can do it all together and avoid some duplication. In the two years or what ever between CS course the students forget much of what was taught so we have to reteach stuff. What stuff? Who knows so reteach it all?

Seems like a pretty serious problem. Fortunately for me I don’t have to solve it for grades K-8. Well not right now anyway. I do have to look at what students entering my high school know though. I teach at a private Catholic school that gets students from over 20 different middle schools in only a few fewer districts than that. These days I can pretty much run my first class is if they know nothing about computer science. That is not going to last for much longer as CS moves into the lower grades. But for the near future there is going to be a wider and wider range of previous experience. That complicates things a bit. A related post is What CS Should a Student Know Before High School

I expect that many high schools will have to have different entry points to the high school computer science curriculum. Some students will want/need to start somewhere between nothing and just a little. Some will have more than a little and even a bit of programming. Still others will have a good bass in programming and will be ready fro one of the Advanced Placement courses.

When students enter high school ready for Advanced Placement or the equivalent we’ll have to think about what to offer them to keep them interested and learning to a deeper level. Wow! Sounds like another blog post.

How do you see the K-12 landscape? What progression would you like to see in your school district or area? How long is it going to take to get to CS at all levels and what sort of changes do you see that making?

Tuesday, June 27, 2017

After ISTE–More Questions Than Answers

One of the great things about ISTE is a chance to talk to people face to face. When that happens a lot of things come up. Yesterday and today, along with walking the exhibit hall and attending sessions, I had some good conversations with people. It all has me thinking a lot. I’m going to dump a few thoughts here and hopefully follow up on them in future posts. Feel free to jump on them now though.

There are lots of things at ISTE for beginners. Not just for the younger grades but for teacher who haven’t taught computer science before. What is there for people who have been teaching CS for a long time and who have advanced students? Not really a lot. This has come up at the CSTA Conference a few times as well but today it struck me that we (the CS Ed community) need to fix that NOW! More on that in a future post.

Here’s another question that comes up. How many times can you teach students how loops work? If we have CS in grades K through 12 what is the sequence? Sure the standards are starting to cover that and the K12 CS Framework has stuff for all grade bands but how does that translate into curriculum sequences? More on that coming to this blog.

All these cool news toys for teaching? Do they work and if so how do we know? Anyone reading know of some research or are we all working on wishful thinking – again? I only have questions on that. I still want to try some of them though. Does that make me part of the problem or the solution? Time will tell I guess.

What should be the role of industry in developing curriculum? I got pretty excited about some of the things I saw from industry – especially from Microsoft. But the question becomes are they just gimmicks or are they the basis for real improvement in learning? Some companies are developing things that are clearly their platform specific – Apple and Swift and other iOS specific tools. Some less obviously platform specific. But clearly industry benefits from more and better trained CS people. Take a look at How Silicon Valley Pushed Coding Into American Classrooms on the New York Times. If that doesn’t raise questions read it again. Personally I see a lot of good coming from industry and Code.Org. But I have concerns as well.

The exhibit hall has a surprising (to me) number of Chinese companies seeing things like robots and 3D printers. Competition is good and I can see this possibly lowering prices. On the other hand most of these products come without curriculum and other things teachers need  for support. Most, though not all, of the American companies understand this and make an effort to provide some teacher support. Some more than others of course. My concern though is bean counters who show based on price alone. Anyone know administrators like that?

I’ve got one more day at ISTE and I am not yet done walking the exhibit hall or attending sessions. Already though I have a lot to think about. And to  think I still have the CSTA Annual conference to attend. If you will be there come find me and help me think about all these questions. If not, drop some comments. Please.

Monday, June 26, 2017

Coding is Not a Four Letter Word

I am at ISTE and have lost count of the times today someone said "you can program this without knowing how to code." Usually they mean this because they use a block based programming environment like Scratch or Blockly or Snap! Well to me that is still coding. Just because the language is not text based doesn't mean it's not real programming or real coding. I come back to the idea that coding and programming can usually be used interchangeably. If anything coding is a superset of programming. HTML is certainly coded instructions but probably not really programming. At least not all the time. Arguably using CSS is programming of a sort. Arguably.

Personally programming or coding, how ever you want to call it, is what I am teaching. If it doesn't need coding than I'm probably not interested. Of course when I talk like that they tell me that I can also use JavaScript or Python or Java or any number of other more traditional programming languages.

Most of these companies are, I feel, really trying to sell some hardware. They must think that coding or programming is scary. Or perhaps that it is too much for someone. For students? For teachers? I'm not sure who. It shouldn't be scary though. It should be empowering. There is a place for block programming tools for sure. But some of us want the power and flexibility to say nothing of the easier transference of skills to other domains that text based programming languages give us.

So don't tell me your device can be controlled without programming or coding because you are using Blockly. That just doesn't compute. And real coding might just be what I am looking for.

ISTE 2017- A First Look

If I am seeing a theme at ISTE 2017 so far it is making. Session after session demonstrates learning by making things. No where is this more true than with computer science. Micro:bit and AdaFruit Circuit Playground Express are being seen in booths at poster sessions and discussed in workshops. Those two seem to be the tip of the ice burg though. This morning I saw a programmable (in Scratch) device that can be inserted in a flying disk.

WP_20170624_17_00_40_ProThe image on the left here shows a “guitar” made from duct tape, cardboard, and a Micro:Bit. The accelerometer in the Micro:Bit means that when the guitar is shaken it plays sounds.

AWP_20170624_16_58_12_Prond then there are these “magic wands” that respond to both movement and sounds. There seems to be a virtually unlimited set of ideas for making smart devices that include the various miniature devices that are becoming available. Microsoft MakeCode is usable to program many of these devices.

One of the cool things about MakeCode is that you can switch between a block like language and JavaScript. That means students don’t grow out of it very quickly – if at all.

What does this mean for computer science? Several things I think. One is that it means we can bring programming to younger and younger students. Most of these devices can be programmed with drag and drop block languages using words that young students can understand. Add to that color and creativity and you have a recipe for keeping lots of students engaged.

But it means something for older students as well. A key thing for getting students engaged is tying their learning into things they are interested id doing. For some that is robots. People who teach in all female environments tell me that women and girls are interested in robots. They just see different robots than boys usually do.

And fashion? NCWIT has e-Textiles-in-a-Box that looks very exiting. Just like robots are not just for boys, e-textiles are not just for girls either. I’ve seen a number of posters involving wearable items that mix electronics and or computer devices with clothing loosely defined.

ISTE is really just getting started today. I expect to see a lot more and will share some of the best of it.

Thursday, June 22, 2017

Student Programmer Fix This Code

Recently I came across this cartoon and shared it on Facebook.


Responses were interesting. The newer one was to programming the more likely people seemed to be to explain why the if statement wasn’t working correctly. The more experienced one was the more likely they were to point out that you probably shouldn’t have written that code (an option to kill humans) in the first place. There is some validity in both responses of course.

In teaching we often create code that is less than ideal to force a particular observation of a concept if less code. How often do we explain that to students? And how well does it take? I’m not sure but it does concern me.

Returning to asking students to debug code. I like the idea and it is something I want to do more of in the future. The problem comes when students don’t have enough experience yet to find the less obvious errors. On the other hand how will they get experience if we don’t let (make?) them practice debugging? Most debugging practice students get is on their own code. Often they are too close to it to see what is wrong.

Last semester I gave students code written by other students and asked them to test it. Most of the code worked as advertised and what students reported out was missing functionality rather than “broken” code. Maybe I need to write some broken code of my own and have students look at it?

How are you helping students learn to debug code? Any ideas to share please leave them in the comments.

BTW there is some discussion if asking students to debug code is better than asking them to write code on the new CS Educators Stack Exchange. You may want to join in there as well.

Wednesday, June 21, 2017

Become A Computer Science Teacher in Five Days

Garth Flint is a computer science teacher in Montana. While most computer science teachers are a bit isolated, most are the only CS teacher in their school. Garth is more so because Montana is a big state with a small population and few computer science t3eachers. Recently he attended a workshop to teach CS teachers. He wrote a review of the experience - A week of in-service: Another Python course

Some of the teachers had no previous computer science background let alone experience teaching computer science. They were mostly told to teach a course in the fall and figure it out.

Only a couple of us had actually done any CS/programming teaching.     It was a bit interesting talking to the teachers that had been give the directive to offer a programming course at their school.  It was a “come up with something” type of directive

I hear this a lot. You know a good teacher can teach any subject with a little prep time. Well no they cannot. Can you imagine asking an English teacher who spoke no French to teach a French course after a one week PD even at a local college? I don’t think so. Why is it less crazy to do the same for computer science?

As Garth points out in his post, teaching (and learning) programming syntax is the easy part but there is a lot more to teaching computer science than programming language syntax. One doesn’t just learn syntax rules and some vocabulary and suddenly speak French. No, there is idiom involved in a new natural language and that is no less true of computer science.

A week long course can give a CS teacher enough to get ready to teach a new programming language or a new curriculum. What it can’t do is really get you seriously into computational thinking or go deeply into the how to teach or why things are done they way they are. There is just no time.

The best professional development for teachers new to the subject are more involved (and longer) than 5 days. They involve pre-workshop work, post workshop work and ideally the workshop[ is longer than a week.  Even then things are going to be pretty tough that first year (or three). What worries me the most about assuming enough can be learned in a week is a) students will get turned off b) students will have to be retaught later (if we can get them in class again) and c) that teachers will get frustrated and quit before they get good at it.

There are many who believe that it is easier to teach a teacher to teach CS than to teach a CS person how to teach. Please do not mistake me for one of those people.

Tuesday, June 20, 2017

Movies for Computer Science Students

Today was watch movie day. I watched two movies that I have been thinking about showing to my computer science students.

The first one I watched was "The Imitation Game" about Alan Turing. Frankly I didn't like it. I like it even less for showing to my students. Why? Because I don't think students will identify with Turing. He is just to weird. Make no mistake I think Turing was an amazing individual and there are lessons in his story. But, well, it just didn't inspire me to want to do things.

The second movie was "Hidden Figures." This one I loved. Even though few of my students are females of color these women are real and normal in ways that Turing wasn't. They had children, families, and were concerned about others. They had things to overcome and fought to overcome them. That is a message that resonates. I think my students will see people to aspire to be like in this movie.

My experience is that students who see stories like "Hidden Figures" see the injustices against both women and minorities. They understand how wrong that treatment was and is. Sure there were horrible injustices against Turing and his death was a tragedy. But his personality, at least in the movie, is not one to make people feel as sympathetic as the women in "Hidden Figures." And the women won! And in their winning they opened the doors for many others.

So what other movies should I think about showing my computer science students?”

Micro:bit Small-board Computer Launches in U.S. & Canada

The Micro:bit (nee BBC Micro:bit) is now available in the US and Canada. This little device has been in classrooms in the United Kingdom for about a year and a half but is only now become commonly available in the US and Canada. Now at first glance this may not seem like a bit deal. It is a little device that must be connected to a larger computer to program. Seems like an extra step.

Microbit%20render%202%20no%20background But it is a big deal and it is more than just a little device. In a word, the thing that makes the Micro:bit interesting is “Making.”   This little device is easily included in little projects that can really interest students. Just programming the device on its own might get boring quickly. It was for me. But including it in a maker space sort of project is a game changer.

Now you’re asking for resources. The device is programmable in a number of languages and tools from Scratch to Python and JavaScript. There is a 14 week curriculum developed for students by Microsoft. Project Lead the Way also has a curriculum. Both are designed around making things that include the Micro:bit.

The Micro:Bit web site has a bunch of project ideas if you are looking for what others are doing. This could be fun!

Wednesday, June 14, 2017

How To Teach Computer Science

I always read articles like this one - The 5 Worst Ways to Teach Computer Science – with some trepidation. I always expect to find out that I’m doing it all wrong. The other thing that always concerns me is that the author will be all wrong. Everyone who knows how to code thinks they are an expert in teaching computer science. Many of them are wrong. But this article is a good one. (In other words it mostly talks about doing things the way I already do them.) I think to most experienced CS teachers it is review. I think it is written for teachers who are new to teaching CS though and it fits that role well.

I do think there is a place for individual projects though. Not every project needs to be or even should be a group or team project. So the second thing that article did was get me thinking about good practices.

One of the worst ways to teach computer science that the article doesn’t talk about is Do Everything On The Computer. I am seeing that that can be a real problem. My teaching focus is always concepts first and while after 40 years of writing code a lot of things on the computer seem obvious to me. Not so the “digital natives” I am teaching. Many of them separate real life from what is going on in the computer.

We think they see them as the same because of the social aspects of computer use we observe but I don’t think that is really the case. Young people see the communication aspect of using computers as somewhat parallel to their real life but that is much different from most computer science concepts.
Take counters and accumulators for example. They don’t think in terms of those computer science type words even though they use both in their daily lives. It’s hard for them to make the connection using code. I have them count a hand full of coins. Then I have a student total the value of the coins. Now we can have a conversation about counters and accumulators in the context of a loop.
Speaking of loops I have students walk as a loop. Walk seven steps or walk to this point – demonstrates counting and while/until loops. I’m struggling with how to have them act out recursion though. Ideas?

cs unplugged
More and more I am looking for kinesthetic learning that gets students physically involved in computer science concepts. There are some great ideas at CS Unplugged which I use with several classes. “Steal from the best” I always say.
We use some exercises from there when we teach sorting, parity checking, and more. They work well and get students involved. Of course kinesthetic learning is far from just a computer science teaching thing. The growth of maker spaces is one newer aspect of it and “making” has some potential in computer science education. We can also connect computer science to other subjects which will help students learn both/multiple subjects.

The important thing is that we don’t narrow our teaching to just lecture and things the students do on the computer. We have to be more interactive and include ways to get students doing things.

Friday, June 09, 2017

What is the purpose of a computer science education?

One of my former students posed that question. He then asked if it were:

  • Building computer scientists
  • Building software engineers
  • Building citizens

Now context is important in this question. At the university level, many schools see the first item as their main priority. Some see the second a a priority but then they may also see software engineering and computer science as very different majors. Where does the third item – building citizens – fit? Recent events (think Volkswagen diesel issues and hacking and more) suggest that building good citizens should have some thing of a higher priority.

At the high school level , where I teach, the questions are different still. We are not, for the most part, trying to turn out job ready CS students. Oh sure, many of my students have gotten summer internships and part time jobs based on what they have learned in my classes. But I’m not trying to make everyone a professional developer. Nor am I expecting the end result of my course to be a serious (for example published) computer scientist. No, high school is more about preparing students to take their place in the world as informed and (hopefully) ethical citizens. I teach in a Catholic school so we are allowed to emphasize values pretty strongly. In fat that is part of our mission.

I see the purpose of teaching computer science in high school as about several things. Not about making professional developers but giving students the tools to understand computers.What can computers do? What can they not (yet?) do? And how do these things impact the world they live in?

I see my role as building enthusiasm for the subject. (See What CS Should a Student Know Before High School) Not every student will major in CS in college nor should they all. But if I can encourage a few smart kids to do so that is great. At least I don’t want to kill enthusiasm that students might have.

I really want to instill some ideas about ethical practice. High school should be something what about citizenship. That  is where I want students to start thinking about the consequences of computer science and what it enables. They really have to understand CS to understand what is happening though. They need a vocabulary and some understanding of basic concepts. They need to be able to participate in conversations intelligently and with some knowledge. And they have to learn how to learn more.

High school computer science is a beginning and not an end in itself. A high school diploma is not a terminal degree. If students are a little more prepared for a world where computers are important we have been successful.  

Wednesday, June 07, 2017

What CS Should a Student Know Before High School

Recently a middle school teacher asked what computer science knowledge would high school computer science teachers like their incoming students to know. The first answer was the obvious “send them with enthusiasm and we’ll work with what ever knowledge level they have.” Pretty unsatisfying. I know because university CS faculty tell me the same thing when I ask what they want. So I had to think about it a bit.

So what would I really like? Well I’d like them to know the way around the operating system they use. Creating folders, moving files, renaming files, connecting a network printer, and connecting to wi-fi. That’s not computer science you say! Yes it is. It involves knowing something about how computers work and how to get around in the system. It will save me a bunch of time and the students some heartache. I’d also like them to have some experience trying things out. They should know were to look for different things in menus, in tools, and online.

How about understanding how the Internet works? DNS, packets, IP addresses, and stuff like that. I don’t mind teaching that. It’s actually fun. But students could learn that earlier.
For programming things? I’d love to spend less time on variables, loops, and decision structures. Can they use them to solve simple problems? Do they understand the connections between a variable name and a location in memory, a variable type and how much memory is uses, and how values are identified? Can they understand how a loop works and how an if statement works? If so I saved about three weeks that I can use for more advanced things like arrays and objects and methods and scope and a whole lot more. Even if they know those concepts in something like Scratch or Alice I can jump right to syntax for text based languages.

Honestly though few of my feeders are going to do all that. So I’ll still need my current freshmen course. But if a couple of kids can jump right into Honors Programming or AP CS Principles I could be very happy.

Thursday, June 01, 2017

Need Funds to Attend the CSTA Conference?

OK this is an opportunity too good to pass up if you are a K12 computer science teacher. Seriously.

If you are a K12 teacher, then Rolls Royce wants to help get you to the conference in STYLE!

CSTA and our partner Rolls Royce are excited to announce a scholarship to help K-12 teachers attend the CSTA Conference in Baltimore, Maryland this July.

Thanks to a generous contribution from Rolls Royce, over the week of June 5 - 9 we will give away a total of twenty-five (25) $1,000 travel scholarships for the CSTA Annual Conference. Each day we will release five (5) scholarships until they are gone.

How do you get one of these scholarships?  Here are the rules:

  • You must be a K12 Teacher to be eligible. No exceptions.
  • You may only receive one scholarship to attend the conference. Recipients of other CSTA conference scholarships are not eligible.
  • Each day by 9:00 AM EST we will post a unique application link for that day via Facebook, Twitter, and other media.
  • Applicants can submit one entry each day. All applications become the property of CSTA.
  • Each day there will be a simple question or activity to complete.
  • Each application will remain open for 24 hours.
  • Recipients will be randomly selected from eligible entries and notified by email.
  • Recipients will have 24 hours to confirm the scholarship or it will be released to another applicant.

Have fun, and we look forward to seeing you in Baltimore for fun and learning at THE event for and by CS teachers & teachers that teach CS!

The CSTA Annual Conference will be held in Baltimore, MD on July 8-11 and we have a great lineup of sessions, workshops, and exhibitors planned.

Click here to find out more about the conference.

Need more information?

How To Make Computers Work For People Like You

Years ago I was giving a career talk in Roxbury (a heavily minority neighborhood in Boston) to a group of students. At the end a young African American woman asked me why I, a middle aged white male was interested in seeing more people like her in computer science. A fair question for sure. My reply was basically that I worked for a company, Microsoft, that wanted to have customers of all types. While I have a pretty good idea of what middle age white men want, young African American women probably have different wants and needs that I don’t know so well. So to serve the needs of diverse customers we really need diverse people in the field.

While that is true now and was then I have sense learned that things are worse than I knew without diversity. Take this article - Algorithms aren’t racist. Your skin is just too dark. – for example. If I am living in an all white world I might never notice this sort of built in bias – intentional or otherwise. It reminds me of other stories I have heard during my career.

A company I worked for created color CRTs where the default colors were red and blue. The developers had no idea how common red/blue color blindness is. And there is thee famous story of the developers who were so proud of the handwriting recognition of the Apple Newton. Until they gave it to Steve Jobs to try. It turns out they hadn’t tested it with left handed people – like Jobs – and it could not read his handwriting. There are more examples out there but you get the idea.

A reason to increase diversity in computer science is so that computers work better for more people. It’s a diverse world out there and we can’t have computers that only work for white and Asian males. Especially not if they are all cookie cutter examples of a few narrow types.

The best way to have a future that is built for you is to build it yourself. With computers becoming more and more central to daily life we need that diversity building out future.

Wednesday, May 31, 2017

News Flash! School and Industry Are NOT The Same

Computer Science cheating has been a discussion lately. Not just in the NY Times article I referenced the other day (Cheating In Computer Science Class) but on Facebook, on Twitter, and other social media. One sort of rebuttal to the concern over cheating was a blog post - Computer science students should learn to cheat, not be punished for it  - that also got a lot of attention. I see industry people nodding their heads in agreement. The problem is that the rebuttal author doesn’t seem to really understand the issue. There are some common misconceptions that I think need clarification.

Misconception: The goal of a school project is a working program.

That is what the goal is in industry. Make it work to spec and make the user happy. That is not the goal, or at least not the main goal, in a school project. The goal in a school project is to demonstrate what a student knows. Not what their friend or their parent knows but what they know. It is a diagnostic tool for the teacher to see how much learning is taking place. An imperfect tool to be sure but all we have are imperfect tools.

We also want them to practice and use what we are teaching. Cut and paste is usually a poor substituted for figuring out how to solve a problem and properly use the tools that are being taught. One learns more by doing than by simple copy operations.

Misconception: Students who copy code have to understand it to use it.

Oh if only that were true. Any teacher will tell you that students use code acquired from others without understanding it all the time. If a student finds a snippet of code, understands it, and uses it in a project most teachers would see that as a win. The student learned something. Wonderful! We’re happy. Using code without understanding it helps no one.

But it is not just snippets that are involved in cheating. Nothing so remotely borderline as partial borrowed code. Sometimes a student will hand in a full and complete program that they found on the Internet. And they will do it without understanding a bit of it. Who does that help? No one. Remember that in school the goal is gaining knowledge not just handing in something that works.

Misconception: Teaches don't want students searching the Internet for help

The internet is a wonderful learning resource. I know teachers who explicitly recommend sites like Stack Overflow to students and encourage them to look there for help. Some of us actually recommend reading the documentation online and even using sample code. As long as the student understands what they are using. Teaching is not just about covering the limited material but helping students learn how to learn. We’re thrilled when students use outside resources to go beyond the scope of the class. But we do want students to understand what they are doing.

Misconception: Programming for school and for industry should be the same

No. In industry the goal is a working program and in school the goal is learning. Industry expects employees to know things. School assumes they don’t and strives to teach things. The goals are different so the methods must be different.

I have heard the argument that schools should teach the things that industry needs using the tools that industry uses. It’s the old trade school mentality. And that works great for trade schools which serve a valuable purpose. Computer science education has to be more than just the tools of the hour. It has to be on concepts that last for a career. And that process is different from short term goals.

Sure using industry tools can be a good thing. And using things like Git and other source code repository/source code control tools is a good thing. Guess what? Many schools do teach those things. In fact arguably more CS departments teach more of the professional skills, especially soft skills, than many outside of education realize.

Misconception: Computer Science and Software Engineering are the same thing

Computer Science is more theoretical and software engineering is arguably more practical. One should not criticize one for not being the other. At the high school level we are not trying to create professional software developers any more than we are trying to create professional physicists or biologists. Rather we are trying to give students a conceptual basis for understanding the world in which they live. Links to more reading below.

I’ll conclude with one more point which I think may be the most important one. We need computer science professionals with integrity. We need professionals who are honest, who are ethical, and who are dependable. Educators care about cheating in its various forms because we value those traits as  much as we value the technical knowledge students gain in our classrooms and labs.  If a student cheats in school will they not also cheat the companies they later work for? I think so. And that should concern industry people. It should concern them a lot.

On Becoming a Better Computer Science Teacher

Andy Ko, Associate Professor at the University of Washington iSchool and Chief Scientist & Co-Founder @answerdash has posted a blog and slide presentation from a talk he gave called How to be a great (CS) teacher. It’s the best thing I have read on the topic is quite a while. If ever. The article is very good but I recommend you read and save to re-read the slide presentation.

I wouldn’t say that all or even most of the ideas in it are new to me but they are explained very clearly and backed up with references. That is especially cool in that we often adopt ideas without real research behind them. Research is good.

Over the years I have learned a lot from great teachers. Many years ago Carnegie Mellon ran summer workshops for CS teachers where one of the goals was to help us learn how to teach to a more diverse (i.e.. female students and other non traditional) student body. The 6APT program was a game changer for me.

When I was at Microsoft I was able to travel and visit a lot of teachers around the US. And attend a lot of great conferences (SIGCSE, CSTA, and more) Since I returned to the classroom I have tried to adapt many of the things I learned in those years to my teaching practice.

This summer as I put my plans together for next year the ideas in Andy Ko’s work will be a regular reference as I look to how I can improve next year. Always be learning.

Tuesday, May 30, 2017

Cheating In Computer Science Class

An article about cheating in CS classes from the New York Times (As Computer Coding Classes Swell, So Does Cheating) has been all over my social networking feed this last weekend. Harvard’s famous CS50 is the big name example in the article. I wonder if this points to a problem we may be crating inadvertently. Are we creating an environment where taking a CS course is seen as the end product rather than actually learning computer science?

Has taking a CS course become the cool thing to the point where students without real interest in the subject take the course (or courses) more as a resume builder than as a real attempt at learning something valuable for the sake of using it?

The article points out that a CS class can involve a lot of work. This often leads to cheating in many subjects. After all the end goal of taking a class for many students is to get a good grade. Oh sure there are courses where a student may really be interested in the topic and wants to learn as much as possible. But there is only so much time in the day so if a few corners are cut for the sake of a good grade outside the student's real interests what’s the harm? (Or so the rationalization goes.)

My experience is that other students get very upset when their peers take shortcuts. It’s unfair if someone gets grades they don’t deserve. It makes me wonder if grades hurt more than they help. The same motivation seems to lead to cheating as often as it does hard work.

It’s actually somewhat more complicated in computer science though. There is a fine line between collaboration and helping ones peers and actually cheating. Where is the line to be drawn? Once in industry the motto I heard often was “steal from the best” and code reuse was touted as a very good thing. Of course one was always expected to really understand the code they reused. And one usually learned from it. A course is a shorter term thing though and one can sometimes borrow code without understanding it.

What is the answer to cheating? For some it is better detection of cheating and swift, firm, and noticeable punishment. An other option is projects that are more tuned to student interests. It can help if the student becomes more interested in completing the project and learning what they need to know to do so. But it is hard to come up with projects that motivate every student. Especially in a huge auditorium course like CS 50. High school teachers may have it easier there. BY degree at least.
Maybe part of the answer is less focus on grades. That’s hard though. High school students are told over and over again that good grades get them into a good university which will get them a good career. Not good learning – good grades. The words we use matter.

Clearly I don’t have a final answer. No teacher does and we have been dealing with this issue probably as long as we have had grades that matter. For now I find that semester projects of a student’s choice work best. They don’t eliminate cheating. But I think they reduce it. And that at least is a step in the right direction.

FWIW here is a contrasting view - I reply to it at

Wednesday, May 24, 2017

Interesting Links 24 May 2017

It’s been a while since I posted one of these collections. And I’ve been blogging a lot less lately. Call it a sort of blogging vacation. I just needed to prioritize other things for a while. We’ll see how things are going forward. In any case I felt like I had a lot of things I should share so here we go.

I know a lot of people are using Python these days and with summer coming you may be looking at projects for next year as I am. So I thought I should share this Collection of free Python lessons (Shakespearean Insult Generator, Magic 8 ball, Sorting hat, Mad Libs, and more) I’ve used similar projects with students in other programming languages and they work well with students.

Announcing Microsoft MakeCode for Circuit Playground Express – From Microsoft Education. The really cool thing about this online development tool is the variety of interesting and inexpensive hardware it can be used with. Combining programming with “making” opens some really interesting possibilities.

Speaking of making – this look at what Doug Bergman is doing with his students is really impressive. A spirited teacher reshapes the computer science classroom for 21st-century makers He has a very interesting computer lab with movable tables, lots of interesting hardware (think several kinds of robots plus Kinects) and really lets students get creative.

Researchers unveil new password meter   - security is getting more and more attention lately so this information about good passwords may be a good discussion starter. The source code for this password meter (it’s in JavaScript) is available.

The ACM Code of Ethics, Draft 2 is now available for comment. Deadline for Input Is June 5th, 2017. This update is designed to make sure that the code is current with the technology. I plan to have some discussions about ethics based around the final document with my AP CS Principles class. I will at least bring it up in the rest of my courses though. Ethics is VERY important and getting more important to teach all the time.

From the UK there is a new edition of Hello World magazine out *now*. Download via   Brought to you by Raspberry Pi, CAS and the BCS Academy. Lots of awesome in this edition. Things are really moving in CS education in the UK and the rest of us should take advantage of the resources.

Check out the Computational Thinking Interview Series from  CSTA “The CSTA's Professional Development Committee is gaining perspectives on computational thinking by meeting with leaders in the field. In this interview series, we are asking, ”What is computational thinking?””

Designing a Computer Science course with constraints  by Mike @zamansky is a good look at how teachers often have to deal with constraints outside of their control when designing a course.

Three Computer Games That Make Assembly Language Fun – They’re not free but they’re not all that expensive either. Some interesting possibilities for some classrooms I think.

Acer Windows Mixed Reality Headset Developer Edition is one of two mixed reality headsets offered by the @MicrosoftStore Available in August when birthday comes. Seeing these inspired a blog post of mine. A post with some ideas and questions I am still looking for feedback on.

Using Virtual Reality for Teaching Computer Science

    Thursday, May 11, 2017

    Using Virtual Reality for Teaching Computer Science

    Maybe you can help me? My gut tells me that virtual reality or even mixed reality can be useful for teaching computer science. How to do that is the question. I don’t want it to be just another device that students program. That’s not really innovative. I want to think of ways that help students learn computer science. I want them to “see” things that can not ordinarily be seen.hololens-military

    My first thought was a virtual tour of a computer. While I do show students mother boards and other pieces of computers wouldn’t a “walk through” of a virtual computer be better? More interesting? On one hand a video, perhaps just an animation, can do that fairly well. On the other hand virtual reality is the opportunity to take different paths through the computer to trace things the way a student would like. A mixed reality tool would label items as a student looked at a physical device. Taking the tour would be more fun though.

    How about following instructions as data through the pipeline in a CPU? That could be fun and make things more real to students. In fact a general walk through a CPU could be good. The improvement over a simple video would be the ability to travel non linearly. IS that enough? I’d like to find out.

    How would virtually tracing the path of code in a program work? Could we set things up so a student could follow (visually) a variable through code to see what happens to it? Perhaps watching the variables as they appear (are instantiated) and disappear (as their scope expires)? The idea of being mixed in with the code ala TRON or The Matrix has a certain appeal to me.

    Do these ideas make sense to people? Would they help? Do you have other ideas?  Is this even possible with current technology? Putting this together probably requires some talent, time, and even money. Who will do it first?

    Monday, May 08, 2017

    Pseudo Random Numbers Are Confusing

    Random numbers are really useful in computer science. We use them a lot for simulations (or games – pretty much the same thing) and to make programs more interesting. But they are not as simple as might appear. First off they are not really random and secondly there are often timing issues. And then there is the whole testing situation. randomnumber_wordle

    Let’s start with the first of these. Those of us who understand random numbers in CS understand that it is impossible for computers to calculate truly random numbers. Cryptography which really relies on true randomness uses all sorts of tricks and tools to generate groups of random numbers. No serious cryptography person would use a standard library for use in cryptography. But for most things we do  in high school computer science built in library random number tools are just fine.

    Where things have gotten complicated for my students lately is with timing issues. The libraries we are using use time from the computer’s clock as a seed value for the generator. If you instantiate two different random number objects at the same time, or rather within a single clock interval, you get two lists with the same values. Whoops! This is pretty much the opposite of what students really want. They’re generally better with one variable than with two but that is not obvious to many beginners. After all if one is good two is better right? And even if you have one variable if you instantiate it over and over again in a tight loop you can also get a lot of duplicates. Various languages have various ways around this (static variables for example) but hardly obvious to a student who just heard (or read) about generating random numbers.

    And then there is testing. Oh my. Seldom a student strong suit. After all if it compiles isn’t it right? The special problem with random numbers is how does one test if the data is different all the time? Visual Basic has a Randomize statement that makes things “more” random. If one doesn’t use it than the program will use the same random numbers every time. In other languages (libraries really) one can use a fixed seed value to get the same set of random values for each run. How ever one does it, it is useful to have a known set of data for testing purposes. Talking about this is an important part of the larger issues of understanding random numbers AND of testing program.

    One of my tasks for this summer is going to be trying to document this better for students. I realize that I need to cover this in more depth if students are going to really be able to use random numbers effectively. I can only talk so much in a single semester course. Perhaps if I provide supplementary reading for homework it will help. It’s a theory.

    Maybe I’ll bring into the mix. Looks like some interesting tools there.

    Monday, May 01, 2017

    Punch Cards, Comments, and Learning From the Past

    Doug Peterson, whose blog always makes me think, had a post last week about internal documentation. Specifically things like comments which a lot of the popular block languages don’t really do that well. Of course this made me think about my code and what I teach.

    Punch CardsThe image to the right is some code I wrote in university. Yes, I have a 45 year old deck of punch cards and yes, that is a FORTRAN program. I ran into it while cleaning up this past weekend. Doug’s post had me looking at the code. And the comments.

    The comments  are great. They really let me know what is going on. That’s good because my variable names are horrible. What ever was I thinking? I’d do things a lot differently today. And in fact I do do things differently today. I have written programs like this one several times and in several different languages over the years. The variable names are much better. We’ll talk about comments in a moment.

    The first time I dug out this deck of cards was some years ago when I tried to rewrite this program in Visual Basic. The comments, one in particular, was critical for me making things work. I use this as an example for my students of why they should comment their code  in fact.

    My most recent iteration of this program has been in TouchDevelop. I’m pleased to say my variable naming is MUCH better now. My commenting? Not so good. Part of the problem is the nature of the language. Comments are supported but somehow I never seem to think of them the same way as I do in other languages. This seems typical of block or drag and drop programming languages. (Doug brings this up which made me really think about it.)

    Of course lack of commenting is not unique to drag and drop programming. Students have pointed out that some sample code I wrote and gave to them to learn from could use a lot more comments. BLUSH They are quite correct.  I really need to fix that. Perhaps I’ll take on as a summer task to well document the demo code I show students. I really should be modeling what I present.

    I do worry that we are losing the focus on internal documentation these days. There is this theory that well written code with well chosen variable names and identifiers should be understandable without comments. Like many theories that doesn’t seem to work as well in practice though. Well, I’m off to comment some code.

    Thursday, April 27, 2017

    How important is the first programming language really?

    We really need people who have never faced a room full of  students in their lives to teach us how to teach computer science.

    Said no CS teacher ever.

    What brought that on you may well ask. Long story. First Mark Guzdial posts about changes at Stanford (Stanford CS department updates introductory courses: Java is Gone) highlighting an experimental version of their first programming course to use JavaScript. Then it hits Reddit (Stanford is moving from using Java to JavaScript for their introductory CS course) where hundreds of comments follow. Yes, hundreds. Most appear to be from people who have never taught a class themselves but have strong opinions of what a first language should be. And the occasional journalist kicks in with something like Universities finally realize that Java is a bad introductory programming language

    How ever would we poor ignorant teachers get along without these experts? Fortunately for my sanity Mike Zamansky who actually is a teacher jumps in with some useful thought. A new first language? What's the follow up plan?

    I believe that a first programming course is very important. The language used, while important, is not the biggest consideration. Rather is is the concepts covered (see Mike’s post) and how well the instructor does in preparing students for what comes next. The new course at Stanford is going to be taught by Eric Roberts who is one of the al time outstanding CS educators. I’d sign up for that course because of the instructor even if it was in COBOL.

    Teacher is important. Curriculum is important. Projects and assignments that help learning are important. Language some where down the line.

    I figure I’ve learned a new programming language about once every three years for the last 45. While I joke that I can still write a good FORTRAN program in any language the truth of the matter is that learning new languages changes how I code and how I think about problems. The first language got me hooked. But that was not the end all and be all. The first course is just the first course. There is a lot more to come and it would be a mistake to try to cram a four year undergraduate curriculum into a one semester (or even full year) high school course. And yet that is what some "experts" seem to be trying to do.

    Wednesday, April 26, 2017

    Surface Book–a first look

    I’ve had two Surface Pros. A Surface Pro 3 and a Surface Pro 4. I love them. Make no mistake these have been idea travel computers for me. And powerful enough for just about everything I could want. They are also great for teaching as I can carry them around the room, use the tablet, and project wirelessly to my LCD projector. But I have had my eyes on the Surface Book for a while.

    And now, thanks to the MIE Expert program and the Surface Experts program ( I just received a new Surface Book. As someone who teaching computer science this means three things for me. 1) More disk space - more VS is being installed now 2) more memory (8gb) so emulators should run better for mobile development 3) a faster CPU.

    Actually the more memory means the most to me. More disk is a close second. Modern CPUs are fast enough for just about everything I do. Also the screen on the Surface Book is larger which is also a nice thing.

    As I said though memory and disk are big plusses for me. I’m not your average classroom teacher. I like to install lots of software (I’ve had as many as three versions of Visual Studio installed at once in the past) and I always want to try more things. The disk space on the Surface Pro limited me a bit. The Surface Book has twice as much disk so I have installed a bunch of Visual Studio things to play with. I may not need it all for teaching but I do for learning.

    Memory is the next big item. My Surface Pros have 4gb of RAM. I can run mobile emulators but barely and I have to be very careful about what else is running. With the Surface Book and its 8gb that problem goes away. With my computer lab being updated to 8gb systems over the summer I now have a lot more options to my Mobile Development course next year. To say nothing of my own “needs” for mobile development.

    The look of the Surface Book is nice as well. I’m not big on esthetics of computers but having a nice clean design is nice. I understand the keyboard (a very nice friendly keyboard BTW) comes off but I don’t need that very often. And I still have my Surface Pro 4 if I do.

    All in all I am very happy with it so far. It’s everything the Surface Pro is but more. Just what a computer science teacher who can’t stop trying new things needs.

    Wednesday, April 12, 2017

    Code Slow Finish Fast

    Looking through student code today brought this quote to mind.

    “I didn't have time to write a short letter, so I wrote a long one instead.” Mark Twain

    Students are always in a hurry to write the code for programming projects. No matter how strongly I suggest they think about the problem and design their code most of them start coding right away. This often results is a lot of code where a small amount of code will work just as well if not better.

    Often the techniques for less code require a bit more thought. Setting up a long set of if statements with a bunch of different variable names is tedious but doesn’t always require as much planning as setting up an array and loop solution does. Students are in a hurry so they take what they think are shortcuts.

    Experience tells of course. My version of Whack A Mole (our current programming project) can be changed from 5 possible “moles” to 6 by changing one 5 to a 6. Some of my students would have to write, well let’s just say I don’t want to do the math.  We’ll go over the options during our next class. The theme will be to think more before starting to code though.

    Tuesday, March 28, 2017

    Math vs Programming

    MathTake a look at these two equations. I found the first one on Facebook. The second is my first attempt at rewriting it for the computer. What is the answer?

    Well the first answer is 1. The second answer is 9. How is that possible? If you think about it there is a sort of implied parenthesis around 1/3. It’s pretty clear in the more traditional mathematical expression that one is to divide by one third and not 1 divided by three. imageA more accurate expression for the computer would have some parenthesis to make things obvious. That would give one the answer 1 that the traditional expression provides.

    We see this sort of thing a lot – students assuming that equations in programming are exactly the same as the mathematical expressions their are used to using.  The most common issue is students thinking that the = sign allows copies from left to right as well as right to left. After all in mathematics the = sign means that both sides of the equation have the same value. That is not the same think as the = sign meaning copy the value on the right into the location on the left.

    Some functional languages do things differently. The WeScheme IDE and DrRacket used by Bootstrap for example. That curriculum takes a much more algebra focused look at computer science. Or is that a more computer science focus approach to algebra? Either way it seems to be very effective. (Note that Bootstrap training is available though CSPdWeek and other venues.)

    Those of us using other platforms though have a lot to contend with as we teach students how to build expressions that mean what students think they mean. Is it worth the effort? I tend to think so. But it is confusing at times.  Days like to today make me rethink things.