ok so the first thing you need to do is get all the things you need a small plank of balsa wood, a 2 volt motor, 2 small hollow rods that you can cut, a bunch of wires, some wire clips, a non hollow rod that a small gear can go around all so a small gear and a nether one that the can go on the motor, some thing to prop up the panels on the car and 2 solar panels and tape and some thing to make in to wheels legos are good for this
next take you wood and attach the two hollow rods to the plank
then you put in the rods then put on the wheels but befor you put on the for the back.
fist you should soter on some wires to the solar panels
then you put on to a the rod a gear then put on the wheels.
next hot gun the motor to the to he wood and put a gear on the motor have the gear go straitly on to the other gear
take the solar panels and prop them up with what ever make it so the sun will be on it for as long as it can
then put the wires in there clips like this (+ +) (- -) the atake those to the motors prongs
then let it fly so to speak