Completing each of the following tasks will give you a secret character. There are four hidden characters in the game.

1. Get an "A" rank on each level and track in the "Street Work" mode.
2. Get an "S" rank (get over 40,000 points in Street Work) on each level and track in "Street Work" mode.
3. Complete each level and track in "Time Attack" mode within the time limit.
4. Get a "Perfect" rank on each level and track in "Coin" mode.

Hidden Boards

First you must unlock all four hidden characters. Then, at the board selection screen, press Up, Up, Down, Down, Left, Right, Left, Right, B, A. Now you have 4 new boards!

Ika-Chu (Double Jumps)
Father (More Air Time)
J-B (Press A + B for Turbo Jumps)
J-Arm (Extra Turbos)