Press Square and X while at the Character Selection screen after getting 30 licenses in Arcade Mode.

Unlock All Levels

While you are at the Title Screen, press Up (3x), Down (3x), Up, Down, Up, Down, Up, Down, L1, R2.

Unlock Hard Mode

Press Circle while at the Stage Selection screen after getting 36 licenses in Arcade Mode in Normal Difficulty.

Unlock the Cartoon Board

Get a Gold Medal five times at the St. Competition in X-Games.