Turning your fitness routine into something playful is a simple way to make sure you stick with it. “It’s not rocket science; if something is drab and boring, you’re not going to want to keep doing it,” says Prevention’s fitness expert Chris Freytag. But make it fun, and you might actually look forward to it—or at least be less likely to skip it.  This week’s exercise takes you back to recess with a classic kid favorite: hopscotch. But don’t be fooled by it’s fun packaging; this move is actually a thigh-toning, calorie-burning, plyometric exercise in disguise.  “I’d much rather play hopscotch than do a series of jump squats,” Chris says. “The mental imagery of picking up a marker on the ground ensures that you’re getting the right range of motion—which means your muscles are working harder—without feeling like work.”  So unleash your inner kid and turn your workout into a mini recess. Your butt and thighs will thank you. More from Prevention: 8 More Fun Workouts