Anybody remember Logo, a teaching language from the 80's? Its big plus was
that you could use it to drive a 'turtle' around the floor and draw shapes.

ISTM that Ruby would be an ideal environment for this - either using a
graphical display plus an irb-like shell at the bottom of the screen, or
indeed controlling a real robot turtle.

    fred = Turtle.new
    fred.pendown
    3.times { fred.forward 50; fred.turn 120 }

And of course,

    fred = nil
    GC.start

would make fred disappear into thin air :-)

But unlike Logo, this would be an introduction to a "real" programming
language. Does anything like this exist already for Ruby?

Cheers,

Brian.