text: how can i make a propelled model car using only household materials? i can only use things from the house, like bottles, jar lids, straws, etc.  nothing can be from a kit or anything like that.  please help! use a rubber band.  affix the front of the rubber band to the front of the undercarriage, attach the other end to the rear axle.  when you twist the wheels backwards, you cause tension in the rubber band.  when you let go, the car will move forward until the rubber band becomes relaxed.