Jimmy Neutron: Jet Fusion Gameboy Advance Cheats and Tips

At the Main menu select Passwords and enter the following codes to unlock the corresponding level.

Unlock Levels 1-4 (World 1):

4!6F28X5

Unlock Levels 5-8 (World 2):

XVTC9FJ9

Unlock Levels 9-12 (World 3):

31CX8442

Unlock Levels 13-16: (World 4):

3P!76232

Unlock Level 2:

Z91td?93

Unlock Level 3:

H9g!pzqg

Unlock Level 4:

D9f5Q?p3

Unlock Level 5:

9!!jf93s

Unlock Mystery Level:

9!!8f93s