Ewok Celebration Music:
At the options screen, press Up, Up, Down, Down, Left, Right, Left Right, B, A, Start using the D-Pad. The Ewok Celebration Music should start to play.

Furfill the three bonus objects of the last mission you played:
Enter the code YUB YUB to fulfill the three bonus objectives of the last mission you played.

Get Unlimited Ammo:
CHOSEN1 is the code to get infinitie secondary weapons and lasers
Source: Nintendo Power

Invincibility Code:
Enter in code screen 1WITHFORCE for invincibility.

Play as a wookie in the Jedi Academy:
FUZZBALL is the code to play as a wookie in the jedi Academy
Source: Nintendo Power

Play as Battle Droid:
Enter in the code RogerRoger and you can pick a battle droid in the Geonosis Academy

Unlock All Multiplayer Maps:
Enter the code FRAGFIESTA to unlock all multiplayer maps.

Unlock "Making Of" Video:
To unlock the ''Making Of'' video, earn thirty bonus points.

Unlock All Cinematic Cutscenes:
Enter the code CINEMA to unlock all cinematic cutscenes.

Unlock CD Player:
To unlock the CD player, earn thirty five bonus points.

Unlock Jedi Academy map for Multiplayer:
To unlock the Jedi Academy map for multiplayer, earn twenty bonus ponits.

Unlock Raxus Duel map for Multiplayer:
To unlock the Raxus Duel map for multiplayer, earn five bonus ponits.

Unlock Rhen Var Conquest map for Multiplayer:
To unlock the Rhen Var Conquest map for multiplayer, earn fifteen bonus points.

Unlock Sketchbook:
To unlock the sketchbook, earn forty bonus points.

Unlock Team Photos in the Sketchbook:
Enter the code SAYCHEESE to unlock team photos in the sketchbook. You must have the sketchbook unlocked in order for this code to work properly.

Unlock Thule Moon Control Zone map for Multiplayer:
To unlock the Thule Moon Control Zone map for multiplayer, earn ten bonus ponits.

Unlock Unit Viewer:
To unlock the unit viewer, earn twenty five bonus points.

Unlock Yoda for Multiplayer:
To unlock Yoda for multiplayer, earn forty five bonus ponits.