The following are known Action Replay Codes for Curious George 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
1512c095
9e4ea95b
3edb39e5
38227a61

Infinite Health
6d7ca60d
ee231415
3542f0a7
7d2e171f

Infinite Lives
14c5cc6d
556cebd3

Infinite Flowers
8f9bbeb6
ed5f384a