The first difference of course would be the way you play the game on the Wii, and on the Xbox 360 you get an HD version of the game with higher resolution textures, and all the other sharper visuals you´d expect from an Xbox 360 port of the game. Oh and not to forget about Achievements of course.
But the real additions are eight new missions, four new school classes (biology, music, math and geography), new unlockable items and clothing, new two-player offline minigames and new awards.
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