Babies love to kick, and there's a reason: They may be getting those little legs ready for walking, or perhaps just trying out new skills. Prime your budding biped (and liven up diaper changes) with an impromptu horizontal spin class.

Appropriate for: Newborn to 10 months
Skills developed: Gross motor
What you'll need: No equipment necessary

When your baby is lying on his or her back on a changing table or pad, hold his or her legs and give them a little workout. The classic move is the bicycle, but you can also demonstrate the cancan: Raise your baby's knees up and give each leg a high kick.

No need to neglect the arms: Move them out to the sides, then raise them up above your baby's head. (This could be thought of as "the frog.") Finally, don't forget the disco fun of "Y-M-C-A" – babies especially love the exuberance of the arms-in-the-air Y.