Start 'em young

My 6.5 year old son was off school sick yesterday. I decided it's time to introduce him to the joys of coding. What better language than Logo to get someone started. I know, I know, it's really a symbolic processing language with a noble Lisp pedigree and so much more than turtle graphics, but turtle graphics seemed like a good place to start.

We used a browser-based Logo implementation at http://www.calormen.com/Logo. It's a site that won't win any beauty contests, but it seemed fairly functional. I explained the underlying metaphor of the turtle with a pen that can be raised or lowered and showed him how to draw a few simple things by a sequence of commands e.g. fd 100 rt 90 fd 100 rt 90 fd 100 rt 90 fd 100. That seemed to make sense once I explained how 90 degrees meant going from vertical to horizontal. This is the kid who asked me when he was four if two dots could ever make a curve, so I figured he'd be good.

He immediately wanted to try a few things, like moving the turtle forward 1,000. I just let him try and see. Whoa! The turtle goes out of the visible region. We cleared the screen (cs) and tried some more things. What happens if you go forward a really large number like 100000000000000. I was expecting an error but no it just went out of the visible region. What happens if you turn right one degree and draw?

Interestingly he said he was "asking" the turtle to do things although after listening to me referring to "commands" he started to say he was "commanding" it to do things. I left him to experiment on his own for a while.

Perhaps next time we'll do some control structures. Perhaps something simple like repeat 4 [ rt 90 fd 100].