At the main menu, press Up(2), Down(2), Left, Right, Left, Right, Up(2), Down(2), Left, Right, Left, Right to unlock all animals, foliage, buildings, and other objects. If you entered the code correctly, you will hear the sound of an elephant.

Change a guest's name to "Andrew Binder" to unlock all animal houses.

Change a guest's name to "John Wheeler" or "Adam Levesque" to unlock all animal shelters.

Change a guest's name to "Lou Catanzaro" to unlock all animal toys.

Change a guest's name to "Charlie Peterson" to unlock all foliage.

Change a guest's name to "Akiyama".

Change a guest's name to "Bill Gates".

Change a guest's name to "Dr Dolittle".

Change a guest's name to "Steve Serafino".

Change a guest's name to "Zeta Psi".

Change a guest's name to "Mr. Blue".

Change a guest's name to "Mr. Brown".

Change a guest's name to "Mr. Orange".

Change a guest's name to "Mr. Pink".

Change a guest's name to "Mr. White".

Change a guest's name to "Mr. Blonde".

There are four bonus scenarios that are unlocked by completing a scenario on different difficulty settings (beginner, advanced, etc.).

At the credits screen, tap the lion at the bottom of the screen. It will put a piece of trash in the trash can. If you tap it again, it will take it out.