Burr Tools is a set of programs for solving some kinds of puzzles, namely puzzles that are made out of square, cube-shaped, spherical, or triangular units, and whose solution also contains only pieces aligned along those grids. The program finds assemblies for the puzzle and animates how you have to assemble for some of them.
Multiplication Station will teach your child to add, subtract, and multiply. It is a multi-user application with a simple admin interface. All parameters are configurable, like grid size and the fonts and colors of number ranges. A countdown timer is used to keep the player's attention focused. A list of high scores is maintained.