Maglev Cars: What's the Attraction?

The students will demonstrate their knowledge of the basic properties of magnets by constructing maglev cars. They will demonstrate that the North and North poles or the South and South poles of the magnets will repel each other. Using this property students will build cars that will float upon a magnetic field and be propelled down a track by an electric motor.

This is an 8 ft. section of the track. I made 3 sections for a total of 24 ft. of racing length. The total number of magnets used was 600. Each magnet is 2" x 3/4" x 1/4". They're called Domino Magnets.  I bought them on Ebay from a wholesale liquidator who gave me a great deal when he found out I was using them for school. The base for the track is made from 3/4 inch OS board covered with 1/4 plywood (the smooth stuff that's used before you tile your floor). The rails were made from aluminum coil that is used in roofing. A friend of mine owns a break and he bent it for me into the rail shape. A break is a tool that is used to bend metal.

Materials needed for cars:
1" pink rigid Styrofoam cut into 4" x 12" pieces
small electric motor with propeller
2 wires (3 -4 inches long)
hot glue guns
hot wire cutters
utility knives
craft sticks

Measure the distance between the rails and cut the width of your styrofoam block to this dimension.

Tape 4 magnets to the corners of the styrofoam block.

Place the car on the track. Since I have a lot of experience making these cars I can get mine to float right away but the students will not find it so easy. In the first photo you can see that it is barely floating within the rails. If we tried to race them like this they would pop out before getting very far. In the second photo we added 4 washers, one to each corner of the car. In the third photo you can see it levitating with the washers on it.

The last thing to do is to attach the motor and the wires. The motor must be high enough to avoid the track and can be located at the front or back of the car, whatever the student decides. The first picture shows the most basic car. I don't except this car as a finished version. I expect them to modify their cars. The second picture is an example of a modified car. I also have students who make their cars completely out of craft sticks or a hybrid of both styrofoam and craft sticks.
The rails of the track are covered with aluminum tape to make them more conductive. In the third picture you can see how I hook up a variable DC supply source to the rails. The wires from the motors on the cars must touch the rails in order to get electricity to run.

A few hints:
The distance between the rails and the car must be as narrow as possible or the cars will slip out.
If you don't have hot wire cutters to cut the styrofoam small saws work also.
Encourage the students to be as creative as they want.
Buy the styrofoam in 4' x 8' sheets at Home Depot or Lowe's, it's a lot cheaper.