How to Make a Circuit-Powered Car That's Worthy of a School Project

Trace a car base design on the cardboard. Measure and draw a 3/4-inch square at each of the four corners of the base design. You will fold these down to attach the axles onto the car base.

Cut out the base design that you drew on the cardboard with the scissors, with the four squares attached.

Fold the four squares down and mark where the axle will go in the center of each square. Make a small cut with the scissors at these points.

Measure and cut a 1/4-inch piece of a straw. Put a little glue on the outside of the cut straw pieces and insert them into the holes you made in the squares at the corners of the cardboard to create your axle holder. The straw pieces should fit snugly into the holes.

Place the two rubber bands on one of the dowel rods and pull them together in the center of the dowel rod. Insert the other dowel rod into the opposite end of the rubber bands.

Insert the dowel rod through the straws from the bottom center of the car base to make axles that connect the sides of the car, one at the front and one at the back.

Place a small drop of glue in the center of the wheel and slide the wheel onto the dowel from each end. Allow the glue to dry for a few minutes and cut the excess dowel rod off at the outside of the wheel.

Choose the cardboard pieces for the front and back of the car. Pull the rubber bands to the outsides of the axles and glue the rubber bands to the dowel rod axle in the front. This makes the front axle your drive axle.

Place the electric motor on the top back of the car base and tape it into place with the electric tape. Pull one of the rubber bands from the back axle up to the motor and gently wrap the rubber band over the exposed gear on the same side of the motor. Repeat this on the other side.

Twist one wire to the negative terminal on the motor and twist another wire to the positive terminal. Each negative terminal will show a (-) symbol; each positive terminal will show a (+) symbol.

Coil wrap the negative wire around the flat negative end of one of the batteries. Make it tight enough to touch the end and wrap around the sides, but loose enough to slide off. Leave about 3 inches of wire to coil the other battery. Slide the negative end of the wire off in a coil that the battery will fit back into. Coil the remaining wire around the negative end of the other battery. Repeat this for the opposite, positive side of the batteries with the wire attached to the positive side of the motor.

Gently tape one side of the coils to the top of the car with electrical tape. You will have four coils, one coil for each end of the two batteries. Mark the top of the car by the wire coils which end is positive (+) and which end is negative (-) to ensure that you put the battery in correctly every time.

Slide one battery back into the coil on the taped end; then slide the other battery in securely. The motor should start to turn and turn the wheels. To stop the car, remove the batteries from the coils.