How to Make a Bingo Machine

Write the numbers (1 to 75 for standard Bingo) on the balls with the permanent marker.

Heat the blade of the craft knife and use it to cut a circular hole in the side of the hamster ball 1/8 inch larger than the plastic balls. Cut the hole along the "equator" of the ball, imagining that the place points where the ball rests in the cradle are the "poles."

Cut the handle off the tea strainer with the hacksaw. Put a couple of lumps of the pressure-sensitive adhesive on the rim of the sieve section of the tea strainer and stick it over the hole.

Open the hamster ball and put the plastic balls inside. Place the hamster ball into its cradle and spin it. Keep spinning until a plastic ball falls through the hole. It will remain trapped between the strainer and the outside of the hamster ball. Bring the machine to a stop, turn the hamster ball it so the strainer is at the side, horizontal to the table. Pull the strainer away from the hamster ball, carefully cupping the plastic ball.

Remove the plastic ball and stick the strainer back into place. Call out the number and place the plastic ball in the cup to keep it from rolling away. Spin again after the players have marked the number on their cards.