"GCompris is a suite of educational games and activities for
children aged anywhere from 2 to 10. Areas of learning include
computer discovery, algebra, science, geography, reading, and more.
Childsplay is a similar game suite, with two built-in activities, a
memory and a typing game.You can download more games for this suite
on their plug-ins page.
"Tux, of Math Command (TuxMath for short) is an educational
arcade-type game starring Tux, the Linux mascot! The player must
solve the math problems that drop down before they pass up Tux, as
Figure 1 shows, by entering in the correct answers; see Figure 1
for an example. Players can choose to play in the Math Command
Training Academy, where he or she can choose from over 50 types of
math problems, from simple addition to multiplication and division
of negative numbers. Players can alternatively choose the Arcade
mode to be presented with a variety of problems based upon the
level they choose. In addition, you can even build your own custom
games. TuxMath is a great, fun, game that can help even adults
build up their math skills."