Ribbit

Ribbit is a fun little game that teaches kids to recognize shapes. Rectangles, triangles and circles need to be dragged onto the board; gradually revealing the colorful picture underneath. Applause welcomes a job well done if the complete board is cleared and a slide show of attractive animal pictures forms further reward. This Mac OS X app is completely free. Of course it's more fun to play on an iPhone or iPad where Ribbit is available as well.