Great, fun hitting drill: get a few medium sized cardboard boxes, draw a baseball on them & let the kids whack at them. Be sure they use proper stance and that the 'ball' is at the right height. Three pluses: 1) they gain wrist power by hitting the box (follow through), 2) they learn and practice keeping their 'head in' and looking at the ball, and 3) the kids absolutely LOVE bashing a box until it is shredded. We were taught this as early teens and it certainly worked well.