Skipping is a great exercise for working on balance and coordination but its dynamic nature will also improve your explosiveness and get you to think about your foot position when landing.
If you have a skipping rope for this one then great, but if not, then we like to pretend! Hold your arms out to your side holding your imaginary rope - ignoring everyone else in the gym! On both legs, jump and drive your knees up high, then land on the balls of your feet. Keeping your heels off the ground, jump up and down over the rope with fast and light feet.
The main focus is on leaving the ground as quick as you can, the height is less important!