Cheat mode:
Press Left(5), Up(5), Right(5), Down(5), Select(5) at the title screen. All levels and bonuses will be unlocked. To access the sound test, hold A and press Left or Right to make a selection, then press Select to hear it. Select the "Scrapbook" option to view background information about the game.

View ending sequence:
Enter staff as a case-sensitive name. Enter the snack shop to view the ending sequence. Note: This also unlocks the hidden credits level. Quickly jump twice to get on top of the low building that appears immediately before the programmer's credit. Then, jump up and keep jumping to the right on the clouds until you find a hidden message.

400 medals:
Enter xyzzy as a case-sensitive name. Then, hold A and press Select to increase the medal count to 400. Hold A and press Select again to reset the count to 0.