Enter NYOPUGLE as a password.
After you lose all your lives, and get "Game Over", hold A + B at the title screen and press Select 5 times, then hit START. | Submitted by bbjoey
At the title screen, hold Start + A + B.
Right before a round starts, hold START and A to skip to the next level. This only works up to level 16. After pressing start and A, press select and B and you will be able to skip to level 45. | Submitted by bbjoey
In the beginning of the level you want to skip (right after the opening theme music stops playing and the words on screen disappear), press and hold the Start button and (while still holding Start) press the A button and you will skip to the next level. Note: This only works for the first 16 levels.