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cs10 / bjc-r

The Beauty and Joy of Computing public resource repository.
https://beautyjoy.github.io/bjc-r
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Drawing a star #187

Open brianharvey opened 10 years ago

brianharvey commented 10 years ago

The title of this page at the top of the page is different from the title in the navigation box.

Isn't this premature? They've done the self-tests about the Total Turtle Trip Theorem, but there hasn't been any explicit discussion of it. Such a discussion, for example, might include showing an irregular but simple closed polygon, showing the script that drew it minus the input to the last TURN, and asking the students to discuss how they'd find out that last turn other than measuring on the screen. /Then/ ask them to draw a star. (I'd leave out the initial turn to get it right side up; that's just a distraction. But I'm not insistent about that.) And then give a hint (I like to say "Go to the next page if you want a hint") saying "how many complete 360-degree turns does the sprite make while drawing the star?"

xtitter commented 10 years ago

'draw a star' was originally in the 'draw a polygon' step, and I thought it was too difficult. I was going to lose it completely except one of the self-test questions used it.

I think getting into TTTT (first I've heard of that) is too big a distraction -- there are some big ideas to get too; and already too much math; and plenty of open-ended activities for them to spend their extra time on (monkey dance, and draw a field of flowers).

I could put an 18 in that first turn block?

brianharvey commented 10 years ago

I think getting into TTTT (first I've heard of that) is too big a distraction

Then what's the point of all those self-test questions?? Teaching the TTTT is what those are all about. And it's /very cool./ I'm not saying to spend a week talking about this; just, after those self-tests, a paragraph saying "Isn't it interesting and counterintuitive that all the total turnings are 360 degrees no matter what polygon you draw? Do you see why? Pretend the MOVE blocks weren't there, so the whole program is TURNs. Then what the program does is rotate the sprite through a complete circle, so that it ends up pointing in the same direction in which it started. A complete circle is 360 degrees." We used to routinely teach this to first graders; I don't think it's too much math for CS10 students.

Personally I think they learn more from seeing the TTTT than from monkey dance, but that's just me.

And, if you don't like the TTTT, why bother with asking them questions about drawing a star? The point of /that/ activity is that if you take out the MOVEs, what's left is that the sprite turns around the circle /twice/.

xtitter commented 10 years ago

Fine. Too tired to add this during this run of CS10. Refactor this for me in person, and I'll try to fix it at some point.