Monday, November 25, 2019

What’s In A Name?

Naming things seems to be a continual problem with programming students. I’ve written about this before (two years ago A Rose By Any Other Name Gives An Error ). I can’t seem to get a handle on it with students. I think part of the problem is that students are good with ambiguity and inference. If you call a student by the wrong name or a diminutive they don't’ use themselves you may get a correction (think warning in computer speak) but they know who you are talking to/about. Compilers are a lot more fussy.

Case-sensitive languages differentiate between “question” and “question.”  Forget about adding extra letters or misspelling a name.

Somehow students have trouble looking that closely at words. I’m not sure if that is because they are too used to filling in the blanks of misspelled words or something else? I do notice that I see a lot of typos and spelling errors in other written work they do. Even though there are spell checking tools built into editors.

Part of the problem may be error messages. Well, that students don’t always read the error messages is part one. But even when they do the messages are not always helpful enough. “Variable does not exist in current context” is pretty meaningful for an experienced programmer. We understand things like scope for one thing. We also know to look for spelling differences. Students sometimes have trouble parsing that all out though. It is something that comes with experience.

Unclear error messages have long been a problem. I think that maybe it is because the people who write the messages have too much knowledge and so assume too much knowledge on the part of programmers. Then again most development tools are designed for experienced programmers and not beginners.

I wonder if smart IDEs will one day help beginners. Perhaps artificial intelligence modules will look at code and ask “Did you mean ‘Question’ and not "’question?” or “did you forget to declare this variable?” Or even “this variable is outside the scope of where it was declared.” This is the sort of hint that teachers give now.

All in all I think the answer is to make the tools more relatable to the people who use them. Teaching computers, which can be very difficult, seems, some days, to be a lot easier than teaching high school students.

Friday, November 22, 2019

Coding For Fun

As with so many things, it started with Doug Peterson. Doug recently posted about something called 100 days of code. This got me started about the need I feel (some times) to do more coding for fun. Or at least coding projects for my own interest and not for “work” purposes. Next up was Mike Zamansky (yet another good idea fairy whose blog I follow) Mike posted about some text based projects he was introducing to teachers during some professional development he has been running. Links below.

Now I love messing around with textual data. Love it. And I’d been thinking about that already and posted about one project recently. Mike’s most recent post reminded me of something I did “back in the day” when we used markup languages to feed into word processing systems (i.e. before WYSIWYG editors) I created my own concordance of the Bible. It was pretty cool to be able to do something like that. I may have to look for tools to do something similar. Maybe with HTML? We’ll see.

I also have a number of “things” that can be programmed sitting around at home.

The trouble is time. Well, honestly, not so much time as prioritization. There are other things to do. School stuff for example. Grading, lesson planning, and all that. And home stuff like the tables I want to build and the hydroponics system I have the materials for but haven’t built yet. And books to read. I need to be exercising more. And, well, you get the picture.

I suppose I could be coding and not writing this blog post as well. Sigh. I wonder if I wrote a scheduling app to help me out?

How about you? Do you code for fun or for learning (which is fun too) or is coding not part of your definition of fun? IF you do like to code how do you prioritize it? Does 100 days of code appeal to you?

Related Blog posts:

Thursday, November 21, 2019

Teachers Helping Teachers For Free

I understand the appeal of sites like Teachers Pay Teachers. Really I do. Some teachers are awesome at creating resources and the idea of getting paid to share them is attractive to underpaid and over worked teachers. Even Amazon, never one to miss a chance to make money, is getting in the business of supporting this idea (Amazon Starts Marketplace for Teachers to Sell Online Educational Resources) . For some reason the idea of asking poor under paid and under resourced teachers to pay for stuff that I have developed for my own use just doesn’t feel right.

I have no problem with teachers who decide to ask other teachers to pay for resources. I have no problem with people who make creating and selling resources in order to make a living. It’s a free country. I hope they have no problem with me giving stuff away for free.

I made a comment to this effect on Twitter and Mike Zamansky replied with “When I was starting out I only survived by the good graces of more senior teachers who mentored and just as importantly SHARED materials (free of charge). This shows the disconnect between capitalists and educators.”

I think that has been the experience for many of us. We survived and continue to survive because others share resources with us.

I’ve been pretty lucky myself. The first real resource I shared online was a pair of project books for Visual Basic and Visual C#. I got paid to write the first editions. By Microsoft not by other teachers. Teachers got them for free. I subsequently updated and expanded them several times as the software was updated but while the books were still free I no longer got paid to write them. I was and am ok with that. I got plenty of use from those projects myself. The feeling of helping other teachers is a reward in itself.

In full disclosure, I have a couple of self-published books on Amazon now. Mostly because creating hard copy books to give away is more than I can spend. But I haven’t turned down teachers who request PDF versions.

I have also benefited from resources shared by others. PowerPoint presentations, video demonstrations, project ideas, and a host of other resources that people have shared over the years have greatly benefited my teaching and learning.  I am very grateful for those who have generously shared those resources.

One day maybe teachers will not be under resourced and under paid. For now though far too many are. That’s why I think we should do as much as we can to support each other.

Wednesday, November 13, 2019

Not Too Easy and Not Too Hard

We’re covering Classes and Objects in my Programming Honors course this week. Specifically we are learning how to program classes in C# and use them in programs.  The struggle for me is to come up with classes that are interesting to students, practical for them to use, and not overly complicated. This is not Advanced Placement computer science A and we don’t have a whole year for the course.

I start with a simple Dice class. Easy enough as an introduction . I also live coded a Coin class. The difference being that I added images to the coin class to show them that more interesting objects can be used in classes. So what next?

Things I have used in the past include a playing card class. Interestingly enough this has had cultural implications. I have international students who are not always as familiar with American playing cards. But it works. There are a lot of pieces to playing cards and you can do them simply (face value and suit) or complicated (Face value, suit, nominal value – face cards are 10, front and back images, suit color, text names, etc) Methods and constructors can get interesting to say the least. So can creating programs to use the “cards.”

I tried a Pez dispenser class once. I do have a 12 inch Pez dispenser on my desk after all. I’ve done it the simple way with just a capacity value and a current count value. What I would really like to do is use a stack in the Pez dispenser class and have candy objects to put in it. If I were teaching APCS A and had time to cover stacks I would do this for sure. But I don’t.

I’ve thought about revisiting some of the class projects from prior AP courses. Anyone remember BigInt? I kind of liked that one. I did more with the Marine Biology Case Student but my students never really liked it. They called it the DAF – Dumb Ass Fish case study. Both may be a bit much for the time I have though.

I had some fun with a quiz question class last year. Data included the question, an array of possible answers, and an index of the correct answer. I liked that for showing how flexible array parameters could be. A true/false question is just a question with two possible answers. The next design question is of course do you have a simple array of questions or do you design a quiz class? If a quiz class, what does that even look like? Might be fun the have students try that design.

I’m still playing with more ideas. I’ll have to use something tomorrow but maybe the good idea fairy will hit before Monday. Suggestions anyone?

Friday, November 08, 2019

Define Better

Someone posted an interesting question on Facebook.

Is using ++i(pre-increment) better than i++(post-increment) ?

My reply was to ask for a definition of “better.” The Facebook posts have a lot of answers from people who appear to not have written a compiler themselves and who making a lot of assumptions. But the point of this post is not to discuss which option is better for some nebulous definition of “better.” Rather is is to think about asking the question of what do we mean by “better?”

There are a lot of what I call religious arguments in computing. Tabs or spaces, curly braces in columns or have the open on the end of a line, what is the best programming language, and on and on. Most of them stem from differing definitions of “better.”

Sometimes things matter very much at one point in time but not at all later and yet the bias from early days remains. There was a time with memory was so tight that a single character variable name was much preferred to a longer more descriptive name because of the space used. Most of my readers probably don’t remember those days but I do. Fortunately I recognized when the change happened. Not everyone did so quickly.  This is possibly at the heart of some of the tabs vs spaces argument for at least some old timers.

Other issues have become moot or mostly moot because we have so much smarter compilers and interpreters these days. We have long been at the point where compilers write better low level code from high level code than even the best assembly language coders. I seriously doubt that there is a difference between the code generated for ++i or i++ as the incrementor in a for loop these days. Compilers are too smart for that. Compiler writers think long and hard about those sorts of things.

How doubly dimensioned arrays are declared used to make a bigger difference than it does today. I can remember thinking long and hard about how to declare and iterate through two dimensioned arrays. You pretty much had to know how the compiler would allocate memory and what cache would look like to get optimal performance. I don’t think many people think about that today except for the most performance critical applications. Applications we don’t give to beginners anyway. Compilers do a lot of optimization on this sort of process so we don’t have to think much about it. Artificial Intelligence and machine learning (see also AI-assisted Programming) are probably going to make compilers even better than they are today.

Today I think “better” in terms of programming should mean “easier for programmers.” Easier to write, easier to understand, easier to modify, and to allow programmers to think about the end result and not the assembly/machine language generated.  Let the software do what software is good at and people do what people are good at.

Thursday, November 07, 2019

AI-assisted Programming

As I said in yesterday’s blog post,Microsoft has been running their big MSIgnite event this week and making all sorts of announcements. One interesting announcement what improvements to what they call Visual Studio IntelliCode.  The idea is that they are using machine learning to help programmers with writing code. In the latest update are whole line completions and refactoring. Interesting.

I haven’t seen IntelliCode in use before and it is probably because it is not turned on by default. I did some searching and found that it can be turned on as an Extension (I had to search a bit under the Manage Extentions option) and then you can customize aspects of it from Tools –> Options –> IntelliCode. Oh, and you need Visual Studio or VS Code 2019 for this. I am using Visual Studio 2019 Community Edition which is free.

SO far I am not seeing obvious help from it but it may be that I have to do something more complicated in my code or write more code first. It does apparently take context into account for its suggestions and I may not have given it enough yet. But I’ll keep playing. And maybe I should look for some video demos online.

There are other things to think about though regardless of if it has been useful already. What is the training like? The write up I have seen says that it learns from examples on GitHub. Initially that scared me as literally anyone can upload to GitHub. One reference I found said  something about the 500 best repositories on GitHub. What ever that means. And what was the criteria for “500 best?”  What sort of standards will this learning suggest?

Some of the documentation talks about options for using other databases of code to train the system so that businesses can train the AI with their code and standards. As a teacher I wonder if there could be a training set for AP Computer Science A? I think Java is supported with IntelliCode in Visual Studio Code.

No doubt some will complain that it is “too much help” for beginners but I’m not sure about that. You still have to know enough to take or reject suggestions for one thing. And having the computer tell a beginner something like “you should make a method to reduce this redundant code” might be better received than the same comment from a human teacher.

Will this help students learn more or dumb down the process? I’m an optimist and think it will be a good thing. What are your thoughts and concerns?

Wednesday, November 06, 2019

Visual Studio Online–Possibilities for Education?

Microsoft has been running their big MSIgnite event this week and making all sorts of announcements.  One of them was a cloud-based development environment called Visual Studio Online.

OK, that looks interesting and I will probably try it out soon. It may be an answer for people pushed to Chromebooks,  others who are at one to one bring your own device schools, or just want students to wrote programs from home. I wonder how it works on otherwise underpowered older computers?  There is some concern about costs and that is something I need to understand.

Maybe I can find someone with an education focus at Microsoft to explain how it might work cost effectively for schools and students.  Or maybe I can figure it out through all the marketing hype. We’ll see but it sure does look worth looking into in more detail.

Question added later: I wonder if this will let me develop iPhone apps without buying a Mac? Anyone know?

Monday, November 04, 2019

CSTA at 15 #CSTAat15

The Computer Science Teachers Association is now 15 years old. I’ve been a member from the start and I have to say that in some ways it feels like it has always been there but in other ways it feels like it just started.  There was a K-12 computer science education community before CSTA. But it was small and one could easily feel alone. CSTA brought a new sense of community and togetherness. Most of all, perhaps, it brought us organization and a stronger sense of belonging.

There was the CS & IT Conference (now called the CSTA Annual Conference)  before CSTA as well but it didn’t have the same feeling of permanence and sustainability that CSTA brought to it. CSTA brought growth and strength to the conference. It’s been the annual highlight of my professional development for years now. Presenting at several of these conferences has been a huge privilege and honor. And added to my learning as well.

After I left industry some years ago I ran for and won a seat on the CSTA Board. What a wonderful experience those four years were. Hectic as we changed Executive Directors during that time. It was a real time of transition. That wasn’t as smooth as many of us would have liked and I think we experienced some growing pains during those years. We’re on our third ED now but things seem to be well on track. Kudos to the Board (after me) who lead the way through the last couple of years and another ED transition. We have an amazing board at CSTA who work very hard for the membership.

The growth of chapters has been a big part of the CSTA story.  Fairly early on, CSTA developed programs to train and prepare chapter leaders and that has paid off in spades. There are more and stronger chapters than ever before. CSTA is both national AND local and that is important.

CSTA has helped train advocates among teachers and support them locally. CSTA members have advocated, lobbied, pushed, and otherwise promoted CS in their states, counties, school districts, and yes even nationally. Some of the companies and other groups get a lot of credit for the growth in computer science education in the US but the real heroes are individual teachers who alone or with other CSTA members did the ground work to make things happen.

From conferences to board membership to involvement with committees and connections with life long friends CSTA has been an important part of my life. I can’t wait to see what the next fifteen years bring.

Friday, November 01, 2019

Magic 8 Ball and Projects From Real Life

There has been a 12 inch tall Pez dispenser on my desk for a couple of years now. It’s a great visual aid for talking about stacks. Today I got a Magic 8 Ball as well. It turns out that a lot of my students were unfamiliar with this staple toy of my youth. Since I really like using the Magic 8 ball program as a demonstration I decided I really had to get a physical ball.

At this point in the semester we have covered loops and arrays and it is time to make programs more interesting by adding more data. I want to use something that makes sense and is not just a demo without meaning or purpose. Having code you can have some fun with is always a plus as well.

I went to Wikipedia and found the classic 8 ball answers and placed them in a text file. My demo reads the file into an array when the program loads. Once the array is built clicking a button displays a random answer. It’s pretty simple to code and we code it together as a class. Students love asking it questions when we’re done.

Usually I have students add their own answers to the text file and then modify the program to handle the new set of answers. We also talk about different ways this could be coded. What if we didn’t know how many answers/lines were in the file? Would be use a different loop and/or a different array type like an arrrylist? What options (methods or functions) should we use to provide the most flexibility?

This also provides students with some sample code to look at when I assign larger projects and expect them to do much more on their own. Is this a good project? Magic 8 ball says “Yes definitely.”