Making a toy car that moves by itself is not too difficult. You could make an electric powered car, but that would require too much expertise with circuitry. If you make a car that is powered by magnets, all you really need are some magnets and some other household items. Making these toy cars will be a project that the whole family can get together to do and is both entertaining and educational.
Empty out all the matches in a small matchbox.
Insert a small magnet into the box and tape it down with some duct tape.
Cut two drinking straws to measure in length the same as the matchbox measures in width.
Attach the drinking straws to one side of the matchbox on opposite ends with duct tape.
Draw four 10-cm (4-inch) circles onto a piece of cardboard using a compass.
Puncture the centre of each circle all the way through the cardboard to create a small hole at the centre using the compass needle.
Cut out each circle from the cardboard using the scissors to create the wheels.
Insert a toothpick into each of the straws and attach one wheel to each end of the toothpick that sticks out from the straw. If the wheels move around too much on the toothpick, apply a small wad of play dough to the tip of the toothpick.
Place the toy matchbox car onto a thin, flat glass or plastic surface such as a tabletop or desktop. Put a magnet at the bottom of the tabletop so that the pole of the magnet in the car and the pole in the magnet under the tabletop are opposite poles. If the magnetic poles are not opposite each other, the car will jump away from the magnet in a random direction.
Drag the magnet below the surface of the tabletop and the toy car will move by itself.