When your kid was a preschooler, getting him to slow down and sit for even a second was an uphill battle. Now that he's older, it can be just as hard to get him off his duff. That's where trampolines come in. Talk about a workout! Not only do they burn calories like crazy, but they increase endurance, strength, spatial awareness, and balance. And they're so much fun to use that exercise feels like play, not work. Just how much to shell out on one of these babies depends a lot on how much you think your kid will use it. For just over $200 bucks, you can get our pick: a fourteen foot trampoline that will last for a bit and keep your child pretty darn happy. Or, you can get a killer trampoline for five times that cost that will last well beyond when you send him off to college. Either way, be sure to buy a net enclosure to wrap around your bouncing wonder, leave plenty of clearance above (and around!), and limit jumping to one person at a time. Then step back and let your kid get some air!