Wednesday, August 05, 2020

Learning Python Part 2: Distracted by a Turtle

I cracked a book and found out that Python supports turtle graphics. I love drawing pictures with graphics. I have since I was in university. So today I played around with the Python turtle a bit.

Mostly I played with a few of the usual turtle methods and wrapping drawing code inside loops. I had some fun but didn’t learn a lot. I’m not sure that was the most productive use of my time.

It did suggest that using graphics with Python is potentially a way to make learning Python more interesting. I have Mark Guzdial’s book on Media Computation around here somewhere. I’m going to dig it out and see if it the libraries for it will work in my environment.  I want to do more than draw lines.

Tuesday, August 04, 2020

Programming Projects for Learning or Grading

The purpose of school work is to get good grades. Well, at least that seems to be a common view on the part of students. Most teachers will tell you that the motivation for students to cheat is that they are lazy and still want to get good grades.  The recent posts by Mark Guzdial  (linked to at Changing How We Teach Computer Science) have sparked a lot of comments on his blog and on Twitter which had sparked some thoughts on my part.

I have long believed that projects are a great learning exercise for students. I haver become less enamored with them for grading. Cheating seems to show up all to often. Often it is hard to prove cheating because projects are to short, variable names are too likely to be the same logically, and there are limited ways to solve them. I have seen the most creativity and the least cheating (provable or otherwise) on larger projects where students were all doing something completely different.

A common thread in the comments I have been seeing recently is that students cheat not because they are lazy but because they don’t know how to solve the project on their own. This idea resonates strongly with me.  I see a lot of satisfaction on the faces of students who successfully complete projects. They tend to actually enjoy the process when they have success. 

Over the last several years I have increased the number of other means of assessments including multiple choice questions that include reading and understanding code. Comparing quiz results with project results has been interesting. Some students show close correlations between quiz grades and project results. Other students not so much. While I haven’t conducted a rigorous or scientific study by any means, my observations suggest to me that students are copying the projects of others because they haven’t gotten a strong enough grasp of the material. 

I’m pretty convinced that evaluative instruments that require the reading and understanding of code are better tools for understanding what students actually know than looking at projects. That is not to say that looking at projects is useless. To the contrary, students who work hard against the struggle show what they know and don’t know in their code. A project that doesn’t work correctly give a teacher a lot more information about student understanding than a project that works perfectly.

In my ideal world, I would give each student a different project for every concept I want them to demonstrate knowledge of. That is clearly not possible and certainly doesn’t scale to large classes. I’d love to have a way to watch student progress on a project. What do they try and what do they do when things either work or don’t work. I don’t know of a good tool to that right now or even if it is practical. I guess for now teachers will just have to watch students closer.And use other tools for grading and for determining what students actually know.

Sunday, August 02, 2020

Learning Python: Part 1

Python has been on my radar for years but I haven’t really had the motivation to learn it myself. It’s time though for several reasons. Reason number one is that I need a learning goal to keep stretching my mind and knowledge. I don’t have a bunch of students finding new puzzles to solve so I have to make my own mistakes.

First step was to pick a development tool. I have played with a bunch. IDLE, PyCharm, Processing, and some I forget. I didn’t like any of them. So I am using Visual Studio. I expect many to tell me that was/is a horrible choice but its the devil I know so there is that. Many of the tools feel like steps backwards to me. I’ve gotten spoiled by the Intellisence in Visual Studio among other features. IDLE felt like what I used to learn BASIC-Plus 40+ years ago. Anyway, I want to spend my time learning a language not an IDE.

OF course there are two parts to learning a new programming language. Part one is the basic syntax. Part two is the idiom of the language. The first part is easy. The second not so much.

I’ve started with easy stuff. Declaration of variables, simple math, declaration of functions, and control flow. IF statements and while loops were pretty straight forward. For loops are different and idiom rears its ugly head here first for me.

For loops in Python seem to be what I think of a ForEach loops in other languages. Very powerful and useful. On the other hand, how do I do the equivalent of:

for (i=0; i <= 100; i+=5)
or
for i =0 to 100 step 5

Or do I need to use a While loop to do this? Go ahead, show off in the comments and help me out.

String manipulation, one of my favorite things to code, is probably next for me.I think that will be ok.  Lists and dictionary come after that. I think I will have to read up on them as they look to be thought of differently than arrays in the languages I am used to using. They also look like fun and powerful to use. So there is that.

Classes after that. Hopefully that moves quickly.

Once I get some basics down I’ll start looking into various libraries and what not. Perhaps go back to try some graphics in Processing. Is there an equivalent to Windows Forms like I use with C# and Visual Basic? Or do I have to go backwards again to do that?

At least I’m having fun. Now to go crack a book.

Thursday, July 30, 2020

Changing How We Teach Computer Science

I haven't been blogging much lately. I'm adjusting to being retired for the most part but I have been reading and thinking a lot about teaching computer science along the way. Mark Guzdial has been thinking even harder and has posted a four part set of blog posts about the subject.

I find that many of his ideas as close to how I have done things in the past. Of course at the high school level we see a lot fewer students with previous experience in CS than many university faculty do. SO we follow much of his suggestions in proposal #1 out of necessary.

The whole series is worth reading. Don’t ignore the comments either.

Saturday, July 18, 2020

Book Review: Weapons of Math Destruction

Weapons of Math Destruction has been out for a couple of years now and it is one of those books that a lot of people reference. I finally got around to reading my copy this week.  For those of you who are not familiar with it, the book talks about algorithms involving huge amounts of data and how they are used and misused.These WMD are involved in increasing parts of our lives from teacher evaluations, to credit scores, to policing, to getting hired for a job. Companies make assumptions that the algorithms are fair, impartial, and that they get the results they are advertised to provide. Often all of those assumptions are wrong.

In some ways I think the point could have been made with one or two chapters but providing a multitude of examples is definitely informative and convincing. The book is more than a little scary but I think that is the point. We should be concerned.

Those of us involved in computing, perhaps especially those of us teaching computing, need an eye opening book like this. It can help us do better and perhaps avoid some of the unintended consequences that this book so clearly outlines.

I’d love to assign this book as required reading to students. I could probably get away with that at the university level but high school students are both reading adverse and already loaded with a lot of reading. I think what I would do at the high school level would be to place a couple of copies on course reserve and assign specific chapters to individual students to read. I’d have them submit both an oral and a written report of their chapter. Some group discussions would also be a plus. This is a natural for an AP CS Principles course but I think it would fit in elsewhere as well.

We need people in computing who can look at technology and think about unintended consequences and, perhaps more importantly, ask what are the impacts on society of what we are thinking about doing? Is it all just about money and the bottom line or are we actually making people’s lives better?

Wednesday, July 15, 2020

Thoughts on Virtual Conferences - CSTA 2020

The first online CSTA Conference is now about 24 hours behind me. I was fortunate to experience it both as an attendee and a presenter. After mulling it over a bit I have to say it was a much better experience than I expected it would be.

Attending was very low friction. No travel half a day each way (with attendant airfare) no hotel to book and pay for and that is just to start. Attending sessions was easy. No hunting for rooms for example. I have put in a lot of steps in previous conferences going to the wrong room or finding a room at out of the way locations. None of that here. No trouble entering and finding a seat. Or leaving if I wanted to switch sessions. Really very smooth.

Attending sessions was great this way. I particularly liked the chat window as it allowed others to share resources and for more people to ask questions. I hope there is a way to capture the chat session information. I would like to have the comments from my presentation at least.

Presentations were of the usual high caliber for a CSTA conference. Sure some were better than others but over all much higher than some other conferences I will not name. Presenters seemed comfortable presenting online. Some of this may because a lot of us have been doing so for school but the preparation for presenters was really very well done. As a presenter I felt very prepared for the platform.

As a presenter things went pretty well. I had wanted to have a second monitor running but due to some technical issues that were all my fault I didn’t get that working. Let that be a lesson to me. Not being able to see the chat window while I was presenting was a disadvantage but the wonderful CSTA proctor was able to see it and fed me questions as appropriate. Having a person who can do it is very important in an online presentation.

While presenting I obviously could not see the reactions so setting an audience based pace was difficult at best. Attendee questions did help there. I also missed hearing people laugh at my jokes (be they intentional or otherwise). There were some comments in the chat that said people did laugh so that’s good. Presenting online is not as much fun for me as presenting in person. One the other hand, I don’t think any of us presenters would have had the size audience we had online if we’d had the conference in person.

The hopin platform worked very well – flawlessly for me. I recommend it. We had a reception area for finding out what was happening and when. A “main stage” for keynotes, breakout rooms for the concurrent sessions, a networking area, and a virtual exhibit hall.

The networking area was very interesting. It placed you in a session with a random attendee for 5 minutes. Just enough time to meet someone and be very low stress. You didn’t have to find an excuse to “walk away.” I took part a few times but as an introvert I have my limits.

The exhibit hall didn’t quite work for me. I like to look at booths and the physical objects in them. It was great if you like to listen to exhibitor presentations and I know that many people do. So that was a mixed story for me. I would love to know what exhibitors thought of the experience.

I was going to write about missing the “hallway track” in this post but I think that deserves a post of its own. So that will probably show up tomorrow.

Tuesday, July 14, 2020

CSTA Online Conference 2020–Day Two

The first thing I did this morning was to prepare for my presentation. I may have made some last minute changes to my presentation deck.

The first thing I attended was a Birds of a Feather session called White Teachers as Anti-Racist Allies. I listened closely. Living in New Hampshire were we don’t have a lot of people of color it is easy to fall into the idea that race is not an issue. But of course I have been teaching in a school with more than the average number of people of color for the area so I know better. This BoF gave me some things to think about.

I couldn’t focus on anything after the BoF. In all honesty I couldn’t get my mind off of getting myself set for you presentation. This tends to happen to be at in-person conferences as well. I probably missed something valuable but hopefully I can watch recordings later.

If you are interested, my presentation slides can be downloaded from Techniques for Teaching Programming. Someone else will have to review that session. Please be kind.

After lunch was a keynote by Dr. Ruha Benjamin called Keynote: 2020 Vision: Re-imagining the Default Settings of Technology and Society She focused on the intersection of technology and bias. Really thought provoking. She shared a really interesting video called "Racial Sensitivity" from Better Off Ted Recommended. How does data and algorithm incorporate bias?

After the keynote I started with Our Code From Miles Away: CS via Distance Learning, which according to to the slides was going to be about Pear Deck and FlipGrid. The main presenter had some issues with time zone coordination which is more a problem with online conferences than in-person ones. Anyway, I left early and moved to Machine Learning in the High School Classroom. It was well done but jumping in 20 minutes late means I missed some important context. I look forward to viewing the recording from the beginning And reading through the website I linked in the session title.. Not much else I can say about this one I am afraid.

Next up was Git and GitHub: How to Use It, How to Teach It, which was of course about Git and GitHub. This was a very fast paced session by a pair of experts. I learned a lot from this one.

I dropped into Nifty Assignments for my last session of the day.

The archive of CSTA Nifty Assignments is here. Check them out!

So the virtual conference is over. For me there were a lot of great sessions. If you were there, what sessions did you like? Let me know which ones I should look for when the recordings are ready.