When Mitch Resnick was growing up in the suburbs of Philadelphia, he and his little brother were always making up new games. For example, he says, "In the basement, throw a tennis ball so it goes between the pipes in the ceiling for two points, and bounces off the pipe for one point."
His parents were tolerant of their making noise and rearranging the furniture. One summer he even dug up the backyard for a minigolf course. The design process was a matter of trial and error: Could he use soda cans to make the holes? What path would the ball take as it hit various obstacles?