An angle is given. Put the monkey on on the circle at the point that you think matches the angle. The closer your estimate, the more bananas you win! How many bananas can you win in 10 rounds?

http://www.oswego.org/ocsd-web/games/bananahunt/bhunt.html

Click on two cards to turn them over. If they match, they are cleared from the board. If not, they remain on the board. How many turns will it take you to clear the board?

http://www.interactivestuff.org/match/maker.phtml?featured=1&id=13

Students have to estimate the angles needed to shoot each of the planets.
http://pbskids.org/cyberchase/games/anglemeasurement/