In a Jam, push in an open area and just do a bunch of advanced flips in a row. Make sure you keep moving and you'll get more points. And all you need is points! Good Luck!
Play as Emo Crys
Press Up(2), Left(2), Down(2), Right(2) at the "Credits" screen to unlock Emo Crys in My Skate mode.
Play as Jack Knife
Press X, A, X, Y, Up, Left, Down, Right at the "Credits" screen to unlock Jack Knife in My Skate mode.
Play as Jay Jay
Press L, R, A, Left, Right, Y, R, L at the "Credits" screen to unlock Jay Jay in My Skate mode.
Play as Lil' Rob
Press L, Left, Y, R, Right, A, Up, X at the "Credits" screen to unlock Lil' Rob in My Skate mode.
Play as Spitball
Press Up(2), Down(2), L, R, L, R at the "Credits" screen to unlock Spitball in My Skate mode.
The Gap: Pass through garage door
At the start of the level, go to the left until you see a garage door. Go to it. Once you are look directly at it, move and you will go through it.
Easy Jams...