Hints:

Extra Jam mode courts:
     To  get  the 2 hidden jam courts you have to beat all 29 teams in
tournament  play  in jam mode. The two hidden courts are a night court
and a beach court.

Extra Create-A-Players:
     Go  to  Jam Mode.Then go to tournament play. Create a player. Use
him to beat the computer. If you win you will see a screen saying that
you  have more points to spend on your player. After beatin 15 or more
teams,  go  to  bodytype.  You will see AfroMan, Athletic Woman. Then,
after beating all 29 teams, you will see Eagle, Crocodile, Rhinoserus,
etc.

Keep Computer From Scoring:
     Whenever  the computer is about to score pause the game and go to
controllers  then  go back to the game. The computer will have to take
the ball out instead of getting points.

3-Point Cheat:
     While  playing  sim,  get  close to the 3-point line, hold Z then
shute.  If  you  let go of Z right before the ball gets to the basket,
you will make the 3-pointer. (This cheat always works)