How should we teach programming?
One of Shimon Schocken’s colleagues says that “Computer science is a thousand layers of abstraction.” This is quite true, and the same applies for programming.
Recently I’ve been thinking a lot about how we can get more people involved with programming. I don’t necessarily mean programming as professionals, but just to develop enough of an understanding on what software is and how it works. So I wrote a book aimed at teaching games programming in Python to the 9 to 12 year age range (get ‘em while they’re young). In my “Python is the new BASIC” post, (which was a plug for my free, Creative Commons-licensed book, “Invent Your Own Computer Games with Python”) I received this comment:
You know, I took a look at that game book and it struck me how so 1980s the thing was. It brought me down to memory lane.
Now, looking at the alternative (Squeak), which is fully OOP all the way down to the very menus and icons, buttons, which has a much richer environment and is totally ready for multimedia, along with the derived (written in Squeak) Scratch language, I think it’s very bad that we’re returning to Basic.
Kids deserve something better in 2008, and we can deliver it, just as long as we keep our prejudice at bay against Smalltalk (because it really is about prejudice and lack of information).
1980s would be right. I based the book I wrote on a 1983 book that taught me BASIC programming (adding Python’s modern features). However, my book specifically avoids higher-level concepts such as object-oriented progamming, event-driven applications, and graphics. I thought these concepts would hide the actual underlying workings of the programs. By using textual input and output from simple raw_input() calls and print statements, my book could focus on variables, expressions, and flow control. I wanted as little “magic” as possible.
“Programming is a thousand layers of abstractions.” I’ll argue that to really understand software, one has to go down this rabbit hole all the way to the bottom, as far as assembly or machine language. But one doesn’t need to understand assembly (arguably the lowest of the programming abstraction layers) in order to actually write useful software, even professionally. And for the purpose of teaching programming, those layers of abstractions save us a lot of tedious details. The key to teaching programming is to find that ideal middle ground: low enough to pull back the “automagic” curtain, high enough to stay above minutia.
My book aims low. There are already several high-level game engine SDKs and drag-and-drop game creator packages to make programming easy (well, easier). I would lose the appeal of graphics, animation, and sprites, and instead rely on text and ASCII art. I would use function calls and loops, a level below recursion and callbacks but above dread goto statements. The high-level space already has lots of ink or bytes devoted to it already, so I aimed low.
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