Fraction games:
http://www.mathgametime.com/games/ratio-blaster-math-game
http://www.mathgametime.com/games/tug-team-dirtbike-fractions
http://www.sheppardsoftware.com/mathgames/fractions/memory_equivalent3.htm
http://www.visualfractions.com/FindGrampy/findgrampy.html
http://www.visualfractions.com/RenameLowest/renamelowest.html
Fractions/Number Lines:
http://www.mathplayground.com/puzzle_pics_fractions.html
Factors/Multiples:
http://www.hoodamath.com/games/factorfeeder.html
http://www.math-play.com/Factors-Millionaire/Factors-Millionaire.html
Prime/Composite:
http://www.sheppardsoftware.com/mathgames/numbers/fruit_shoot_prime.htm
Adding Fractions:
http://www.math-play.com/fractions-board-game/fractions-board-game.html