Most people who have played with magnets know that two opposite-pole magnets will attract, while two like-pole magnets will push apart. For most applications of magnets, people want them to stick together, but their ability to push apart has bred a type of train: the Maglev. Maglev, or magnetic levitation, trains hover over a magnetic track on a cushion formed by two magnets opposing each other, which significantly reduces friction. To make a model of a Maglev train, you need lots of magnets.
Cut a length of track to 2 feet-by 3 inches wide using your balsa wood or cardboard.
Build walls of the track from the excess material. If you are using Balsa wood, cut four 1-1/2-inch wide strips to run along the 2-foot length of the track, and glue pairs of strips together. If using cardboard, cut 2-foot-by-3-inch strips and fold them along the middle.
Glue the walls of the track onto the track so they are between 2-1/2 and 2-1/4 inches apart along the entire length of the track. The walls should be 90 degrees from the track.
Glue 12 of the magnets in a row along the center of the track. Ensure that all of the poles on these magnets are pointing the same directions. If you have the north side of the first magnet pointing upward, be sure that all of the magnets are north side up. Leave the track to dry overnight.
Glue two magnets to your block of wood. Verify that the poles pointing upward on the block are the same as the poles pointing upward on your track. If your track is north side up, glue the magnets so the north side faces outward and the south side sticks to the wood block. Leave your block to dry overnight.
Place your wooden block, or train, in the track. The magnet should hover over the magnets on the track, guided by the rails on the sides. Push the train gently to send it floating toward the ends of the track.
To make a more train-like model, use a thinner block or a piece of cardboard and glue a model train to the top of it. Alternately, you can shape or decorate the model block to look like a train.