Find a ball and a wall. Kick or throw the ball at the wall and catch it. Repeat.
You could bike/scooter/skate/other-mode-of-transport if you have room.
Just go outside and take walk. You'll be surprised at how many ideas you can come up with for stories/blockland while walking. It's also a good time to listen to all the music you have on an iPod or MP3 player.
Schools made me brain-dead, so that's all I can think of at the moment. If I think of more, I'll let you know.
Also! Don't think that something is stupid before you give it a good hour's worth of time. Before I'd try something new, I'd think it was stupid, even if I'd only done it for 20 minutes. But then I'd slowly start to get intrested in whatever I was doing. An hour later, I wouldn't want to quit.
