:)

Materials we used :
alluminum foil->it reduced the turning of the car... a bit. This was a last minute thing, I could not find anything else to add to the car =(.
knex wheels->the best wheels we could find, plus the weight wasnt so bad =)
BBQ sticks->We wanted to be original =) Its light, and easy to work with
bristle board. WHY? For decoration.
straw-> it let the air esacpe the balloon slower, enabling it to move the car.
rubberband-> to attach the balloon to the straw
gluegun/glue/tape -> Obvious reasons :P
balloon-> used for the "gas" of the car. ( the air escaping the ballon car)

X-PLOSION BALLONCAR ! We fixed our car, and now it goes in a straight line ... (most of the time, still not perfect, but we tried our best =) ) !! YAY.Tomorrow is race day, and we hope our car does well !