Today was Andy the Model PhD student's usability study in school so I went along to help. I must say I was dreading the logistics of it: 20 kids, 10 iPhones, 2 busy teachers, gym kit eating pets and the Scottish climate to juggle! In fact it worked out very well in spite of a few initial problems about the kids not being out of class in time to get ready.
We had the rewarding spectacle of a class of excited 13 year olds zooming around the football pitch running away from invisible ghosts. It's a location aware version of Pacman, so the user plays paman by physically running around the field. A ghost appears on the phone screen and chases pacman, and the user must run to escape it. The ghosts get faster as the player gets through each level. The kids really seemed to enjoy it! They did not have the same problems that me and some other adult pilot testers had with working out which way their pacman was moving and how the real world was represented on screen. It just goes to show why it is worth user testing with members of the target demographic group instead of your dim and ancient supervisor: it can save you some programming work. I was also surprised to see that the kids were really exercising hard! They were out of breath and red faced with effort before the end of the 6 minute initial test. Even although they noticed that it is sometimes possible to evade the ghost by walking, it didn't stop them rushing around at top speed.
As a proof on concept, this is pretty gratifying. Andy's game can make teenagers take exercise while smiling. It's a pity this lot weren't fat to start with, but you can't have everything. :-) Next question: can the game keep them motivated after the initial novelty wears off?