I took the normal car and added a chain inspired by things that people would use for tops.

Kids that are at least eight years old should be able to play with this toy and maybe learn about air resistance and "car mechanics."  Directing the rudder to make the can turn in different directions should be interesting to children.  It would also be fun to provide the car with kinetic energy by pulling on the "chain."  A stronger pull would provide more energy which would cause the car to go farther.  Safety should involve not pointing the car at anything and not getting hair or fingers caught on the chain.  Plastic materials would be ideal.  This construction would involve more gears, so it might be a little more expensive.