Skater jumps are not only great for cardio, but also for your agility. They work your quads, calves, glutes and hamstrings. Here's how to do skater hops:
Start standing with your feet shoulder width apart.
Push off of your right leg and jump to the left, landing on your left leg.
Upon landing, push off of your left leg and jump to the right, landing on your right leg.
Continue alternating for 10 reps (each jump counts as one rep).