Get the other player to crash into your wall in this two-player game. The left (green) player uses A & D keys to turn. The right (blue) player uses the left and right arrow keys to turn.
This is featured on the "Invent with Scratch" screencast by Al Sweigart at http://inventwithscratch.com/tron-game/ Learn to program games with this free online Scratch course: https://inventwithscratch.com/class