Super Monkey Ball

Beginner level 2:Warp To level 5
Instead of going forwards towards the goal, turn around and go up the little point. Fall off and land on a platform beneath. There should be another goal there that warps you to level 5.

Monkey Fight: Super power-ups
You can combine the power ups to create combos:

Big Glove Big Glove = Double Glove
Big Glove Long = Big, Long Glove
Big Glove Vortex = Big, Vortex Glove
Big Glove Big Glove Long = Super Big, Long Glove
Big Glove Big Glove Vortex = Super Big, Vortex Glove

Mini Games
Collect 2500 points in the main game, then choose a Mini Game. It will be unlocked. Collect a further 2500 to unlock another, and so on.

Monkey Fight - Collect 2500 Play Points
Monkey Race - Collect 2500 Play Points
Monkey Target - Collect 2500 Play Points

Master difficulty:
Successfully complete the game under the all three initial difficulty settings.