Things You'll Need
Large piece of plywood
Long nut with bolt
Magic marker or paint
The wheel of chance is a popular carnival game and can be built with minimal supplies and minimal knowledge of construction. The wheel of chance is based on a casino's roulette wheel, only instead of laying on a table with a ball falling into one of the slots, it stands vertically with an arrow pointing to one of the prizes. You can build one of these wheels with fairly easy to find materials.
Remove the front bicycle wheel off of an old bike by unscrewing the axle nuts counter clockwise and pull the wheel free of its support, being careful of the brakes. Get a long bolt that is about the same size as the middle of the wheel. Drill a hole in the center of your plywood board so the bolt will be able to fit through.
Stick the bolt through the hole in the board and secure it with superglue. Threat the bolt through the center of the bike tire and secure with a nut. Do not make the nut too tight so the bike tire won't spin, but not so loose that the tire will wiggle when it spins. You can secure the nut with superglue as well, but if you do, you won't be able to easily remove the tire if needed.
Cut the poster board into a circle the size of the bike tire. Punch a hole in the center so that you can slip the poster board over the nut and bolt. Sections with a marker of the different prizes people can win from your wheel. Be careful not to have too many big prizes on there, since the object of this is to make money rather than lose it. Color the poster board any way you wish. Place the poster board onto the tire and secure with superglue.
Draw an arrow on the plywood board pointing at the wheel with magic marker or paint. Spin the wheel and the prize is given to wherever the arrow points when the wheel stops.