SWAT TEAM (babies)

Make a slit in a tennis ball with a sharp knife. Tie a knot at one end of a piece of string, then insert that end into the ball. Tie the other end to a doorknob. Seat your baby in front of the dangling ball, and let her whack it.

TAKE-AWAY LESSON: Cause and effect. When the ball bounces away, your baby gets the thrill of making something happen. Taking aim will also improve her developing hand-eye coordination and depth perception.