The following are known Action Replay Codes for The Wild Thornberrys: Chimp Chase on Nintendo Game Boy Advance (GBA).
These codes were also known as GameShark Codes and in most cases will work on both devices.

These codes are for the U.S. version of the game.

Master Code – Must Be On
b0f3cd7b
56907219
e30c971d
0f2e4b45

Press AR Button: Refill Health
eee8e14d
cad4b8e8
31cb9052
dfa45b86