Here is a collection of cheats which are enabled by going to the 'Main' menu and selecting the 'Cheats' option. Enter the password without the quotes to activate the effect you want in the game.
Unlock ALL Cheats: Enter the password 'partytime'.
Unlock ALL Levels: Enter the password 'bounce'.
Unlock SpongeBob or Patrick Strong for 30 Seconds: Enter the password 'strong well'.
Move Fast for 30 Seconds: Enter the password 'speedy'.
Unlock Shield: Enter the password 'unbreakable' to get a shield around you.
SpongeBob Wears his Karate Suit: Enter the password 'redspongebob'.
Sandy Wears her Karate Suit: Enter the password 'greensandy'.
Make SpongeBob's Pants and Patrick Fly To enable them to fly over short walls and over gaps enter the corresponding letter which indicates the level after their password. To fly in level 1 enter a, level 2 enter b, level 3 enter c etc.
SpongeBob's Pants Fly: Enter the password 'fly(letter for level)' to make SpongeBob's pants float around for as long as you want.
Patrick Flying with Jet Pack: Enter the password 'jet(letter for level)' to have Patrick fly with a jet pack for as you want.