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Khan Academy: Computer Science

khanacademy.org

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Re: Khan Academy: Computer Science

#91

Post by hsshah »

danso wrote: post #14

I've never used a Khan Academy video but that's out of pure negligence on my part, not skepticism. That said, I have always wondered how effective video is as a teaching tool for programming? I guess when I think about it, it's the same delivery tool as an in-person lecture, but in some ways, more effective since you can pause, rewind, etc. See the comments on this article about how to do a Fibonacci recursive exampl…

Good point. That's why I am big fan of teaching "Computational Thinking" before any specific programming language. Personally used Scratch (from MIT) to teach my nephews and niece. It worked well to cement their core concepts.

http://scratch.mit.edu/ http://info.scratch.mit.edu/sites/infoscratch.media.mit.edu/...

Re: Khan Academy: Computer Science

#92

Post by nosignal »

jcampbell1 wrote: post #35
danso wrote: post #14

I've never used a Khan Academy video but that's out of pure negligence on my part, not skepticism. That said, I have always wondered how effective video is as a teaching tool for programming? I guess when I think about it, it's the same delivery tool as an in-person lecture, but in some ways, more effective since you can pause, rewind, etc. See the comments on this article about how to do a Fibonacci recursive exampl…

Kahn makes a big mistake in pronouncing the assignment operator as "equals" in the first video. The assignment operator should be pronounced as "gets".

I think I'm going to steal this for my Python classes. I usually say "is" or "is now", but "gets" I think is a more adroit phrasing. Cheers.

Re: Khan Academy: Computer Science

#93

Post by wyclif »

choxi wrote: post #13

Khan Academy is interesting but imo it's not complete. Technology enables us to make learning an interactive experience -- either interacting with another person or with a REPL interface (like Codeacademy). Just posting videos online in one place is kind of like the obvious step that took a surprisingly long time to get to. It's definitely a step forward, but I can't imagine people are learning enough about, for exam…

I think if you read the comments here from Khan Academy employees, you'll realise that Sal & Co. are quite aware it's not complete yet. Rome wasn't built in a day.

Re: Khan Academy: Computer Science

#94

Post by flexd »

teach wrote: post #83
kenjackson wrote: post #71

Earlier quoted context omitted.

My students, on the other hand, complete literally 80 assignments before beginning for loops. 80 assignments? What are these assignments? Are you teaching them how to use recursion before looping in Java? I get that Java has some ceremony, but not 70 assignments worth. The first day I learned to program (with BASIC) I learned looping. I didn't know the details of it (like there was an index variable I could access),…

How to use a compiler. Basic shell of a Java program. That statements occur in a sequence. Practice with getting details right. Mathematical expressions. What variables are, and how assignments to expressions differ from formulas (in Excel, say). If statements and conditions. The concept of "incrementing" a variable or accumulators in general. Loops in general. See for yourself: http://cs.leanderisd.org/current/cs1/a…

Your CS curriculum is much better than my schools! I just started my first year of Computer Engineering and the Java course so far is horrible compared to this.

I'm a bit disappointed to be honest.

I am very glad I already have been coding for years because our teacher and the planned curriculum seems to confuse people even more.

I think I will refer some people to your assignments, if that's okay? Hopefully someone can learn more from this :-)

Re: Khan Academy: Computer Science

#95

Post by roryokane »

elviejo79 wrote: post #90
teach wrote: post #69

High school CS teacher here. I really hate taking shots at Khan Academy, because I love what they do and his other videos have really helped a lot of my students in chemistry, economics, etc. However, he's moving through the material MUCH more quickly than I've ever been able to do as a teacher. And I get nearly 5 hours a week of face time with my students. For example, his third lecture is on for loops. My students,…

This goes to prove that java is a pretty bad language to teach pogramming. in logo this is how you draw a square forward 100 Right 90 Forward 100 Right 90 Forward 100 Right 90 Forward 100 Right 90 Then in the second lesson you introduce loops repeat 4 Forward 100 Right 90 End then you ask kids to draw hexagons octagons etc. and they will never forget what a for loop does. Edit changed repeat 8 to repeat 4. Thank you.

You could do that in Java if you just imported a turtle graphics library. A quick search brings up one such library, http://www.bfoit.org/itp/JavaTurtleGraphics.html. I agree that Java is a hard language to learn with, but its faults are not related to being unable to use turtle graphics as examples.

Re: Khan Academy: Computer Science

#96

Post by kiba »

wyclif wrote: post #88
kenjackson wrote: post #87

Earlier quoted context omitted.

Wow. Not quite 80, but still an order of magnitude more than I would have expected. Interesting they learn Swing before loops. For me, the first thing I learned was printing, then goto, then for-loop. Maybe just a function of language you learn with.

Yep, me too. Of course, that was in BASIC around 1983.

I learned ruby in 2006-2005 as my first programming language. I don't remember loop being all that difficult to learn.

Re: Khan Academy: Computer Science

#97

Post by Volpe »

elviejo79 wrote: post #90
teach wrote: post #69

High school CS teacher here. I really hate taking shots at Khan Academy, because I love what they do and his other videos have really helped a lot of my students in chemistry, economics, etc. However, he's moving through the material MUCH more quickly than I've ever been able to do as a teacher. And I get nearly 5 hours a week of face time with my students. For example, his third lecture is on for loops. My students,…

This goes to prove that java is a pretty bad language to teach pogramming. in logo this is how you draw a square forward 100 Right 90 Forward 100 Right 90 Forward 100 Right 90 Forward 100 Right 90 Then in the second lesson you introduce loops repeat 4 Forward 100 Right 90 End then you ask kids to draw hexagons octagons etc. and they will never forget what a for loop does. Edit changed repeat 8 to repeat 4. Thank you.

Repeat 4 (right?)

Re: Khan Academy: Computer Science

#98

Post by mquander »

roryokane wrote: post #95
elviejo79 wrote: post #90

Earlier quoted context omitted.

This goes to prove that java is a pretty bad language to teach pogramming. in logo this is how you draw a square forward 100 Right 90 Forward 100 Right 90 Forward 100 Right 90 Forward 100 Right 90 Then in the second lesson you introduce loops repeat 4 Forward 100 Right 90 End then you ask kids to draw hexagons octagons etc. and they will never forget what a for loop does. Edit changed repeat 8 to repeat 4. Thank you.

You could do that in Java if you just imported a turtle graphics library. A quick search brings up one such library, http://www.bfoit.org/itp/JavaTurtleGraphics.html . I agree that Java is a hard language to learn with, but its faults are not related to being unable to use turtle graphics as examples.

No, you couldn't. Did you look at that link? You have to wrap all this OO ceremony around it.

I don't think it's optimal to make someone type

  class Cross extends TurtleGraphicsWindow { public void myTurtleCmds() ...
at the start of every program when they don't yet have the background to understand what a single one of those words are for. It instills a habit of doing crazy shit mindlessly to try to satisfy the mysterious computer.

Re: Khan Academy: Computer Science

#99

Post by elviejo79 »

roryokane wrote: post #95
elviejo79 wrote: post #90

Earlier quoted context omitted.

This goes to prove that java is a pretty bad language to teach pogramming. in logo this is how you draw a square forward 100 Right 90 Forward 100 Right 90 Forward 100 Right 90 Forward 100 Right 90 Then in the second lesson you introduce loops repeat 4 Forward 100 Right 90 End then you ask kids to draw hexagons octagons etc. and they will never forget what a for loop does. Edit changed repeat 8 to repeat 4. Thank you.

You could do that in Java if you just imported a turtle graphics library. A quick search brings up one such library, http://www.bfoit.org/itp/JavaTurtleGraphics.html . I agree that Java is a hard language to learn with, but its faults are not related to being unable to use turtle graphics as examples.

My point is that there are good tools to learn programming. I think that there are languages in which difficult concepts befome easier to explain. logo being the prime example of such a teaching language.

Re: Khan Academy: Computer Science

#100

Post by pbhjpbhj »

teach wrote: post #69

High school CS teacher here. I really hate taking shots at Khan Academy, because I love what they do and his other videos have really helped a lot of my students in chemistry, economics, etc. However, he's moving through the material MUCH more quickly than I've ever been able to do as a teacher. And I get nearly 5 hours a week of face time with my students. For example, his third lecture is on for loops. My students,…

I taught my 6yo for loops in the first lesson using Scratch, but I think our treatment may have rather less rigorous/complete ...
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