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Tag: compsci

Teaching recursion with Scratch BYOB – take 2

This is a follow up from a post I did about a year and a half ago on using Scratch BYOB to teach recursion. The original way of defining parameters in BYOB were a bit clunky, but it’s gotten much better in recent versions so it seems a good time for an update.

A bit about BYOB
If you haven’t tried Scratch in your intro computer science classes run, don’t walk, and give it a try. It’s early October and our intro students just finished their first pass through a unit on list processing. There’s no way we would be where we are if we had to worry much about syntax, and Scratch takes care of that by letting students drag and drop pieces together rather than worry about classes, methods, braces, and semicolons.

Teaching recursion with Scratch BYOB

One of the biggest limits we came across teaching with Scratch this year is the inability to write methods and use parameters.  Methods, returns, and parameters are probably the only major concept in our intro CompSci class that we can’t teach in Scratch; so we introduced them in Alice this past year.  It worked ok, but we haven’t been able to come up with any really good labs that explain the purpose of parameters well to the students.

This past week I came across an extended version of Scratch called Scratch BYOB, or Build Your Own Block.  And it does exactly what I was looking for.  It gives you the ability to create methods and optionally include parameters.

Don’t “unplug” your students

Came across this post from a technology teacher in Cedar Park, Texas.

Much of what she talks about is the result of a conference she returned from in Austin a couple weeks ago.  A conference that I, along with a few thousand other technology teachers, was also at.  I even got talked into presenting a couple of sessions.  One on Python and one on Alice.

Her point, and one I definitely agree with, is that as teachers we don’t embrace technology when it can be used to enhance the education of our students.  I teach computer science so we’re on the computers most every day.  But there are subjects that are not forced to use technology, and many times they don’t.  And that’s unfortunate.  Students are online pretty much 24/7.  Even when they’re sitting in class and supposed to be paying attention to us they have their cell phones in their pockets receiving text message from friends.