:)

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 !

SCRATCH THAT OUT !!!!

AND SO WE CHANGED OUR IDEA.. WELL, we're trying something different, because our car wasnt travelling in a straight line because of the balloon, it was because of the CAR ! the car's point at the top was not straight therefore making the car travel towards the left. AND SO, trying to fix that problem, we sketched a new car, using the same material. BUT if this car doesnt work we will stick to the other design and redue the whole car, making sure the measurements are correct and accurate

STOP... I HAVE AN IDEA !

We just decided to change our idea.. well a BIT, we discovered that our balloon car was a BIT TOO heavy, so... here are the changes :
1. took out one wheel, to make the ballon car have THREE wheels.
2. you know that red part you see in the picture of our recent ballooncar ? The one that is attaching the wheels to the car? We changed those knex parts to bbq sticks ! AND OBVIOUSLY it reduced the weight of the car by a lot :)