Mischief Makers
New World
You're probly wondering about those Gold Gems in every level. Each one acts as one minute added to the "ending". If you can get all 52 gold gems in each level, go to the ending and watch the WHOLE thing, even that suprise ending after the credits. Instead of having the "credits" at the end of the last bar of levels, press "R" for 12 new levels.
 New World
 Skip the Intro
 Sound Test
 Speed Demon
Skip the Intro
To skip the level introduction, press the Z button.

Sound Test
Hold L+A+C-Left+C-Right and press Start at the title screen.

Speed Demon
In the running events of the compettion press RIGHT on the direction pad very quickly to win the race. Pressing C-Right won't work.
Credit Goes To: IGN 64