I have to agree with you about how games are especially good for teaching things that require repetition. I have used card games like 21 to teach addition and subtraction as well as prediction skills. Yahtzee is also a good one for addition and prediction. The online versions are just as nice. My children have a good grounding in basic math skills because of it. Matching games are great to teach categorization, and the puzzle inlays and other online matching games make children want to learn. There is instantaneous gratification through the bells and whistles that are built in. Being able to beat the puzzle or game seems to help with internalizing the gratification and decrease the need for external gratification from peers and authority figures.