HoDoKu - HoDoKu is a sudoku helper written in Java and available in English and German.
I Know It - "I Know It" is an online game for practicing primary-level math concepts.
Minimal Sudoku - Minimal Sudoku is an easy to use, clutter-free classic sudoku game which is designed for iOS 7.
GCompris - Educational Game for Children 2 to 10 years old.
Yasminoku - Sudoku game and solver totally written in DHTML.
Math Games - Math Games is a website which kids in Preschool through 8th grade can practice math.