Level 10:
Hold A and press Start when selecting a level to begin game play on level 10.

Extra points:
Allow the demonstration mode to run. Press Start while the screen is blinking after the CPU forms a Tetris. Begin a game to collect the points from the demonstration game.

Restart with points:
After getting a Tetris during game play, press all the controller buttons to reset the game. Your next game start with the points from the previous game.