To assemble the model, take a simple small electric motor with an axis, which you then put on the wheel; click on a computer mouse. long enough cable and housing for a car that can be any way you want it to be.
Take two small wires and a soldering iron, solder them to the button. The opposite end of one of the wires solder to the motor, and the second to the positive pole. The third contact is already on the motor negative terminal.
To make the machine go backwards and not be limited only to the front, repeat the same steps with wires on the second button from the mouse.
On the prepared in advance the battery connect the plus and minus. Take two batteries, one for each button. Do a control – a basis for batteries and buttons.
When everything is ready, make a case for the car, put on the axis of the motor, the wheels and check the assembled structure. At the push of a button the machine should go forward, and if you press another back.
Based on this simple pattern you can make a more sophisticated car on the remote control or connect your imagination and invent new and exciting solutions.