we did the hospital challang how ever we never got to do it. We used a standard car then added on to it it worked but we ran out of time. The reason we ran out of time is that we adjusted car parts and cheakead the weels the weels wernt working because are car whent to fast the hard part of the challange was getting it to slow down for when it had to stop. I had the most fun doing was geting the mising peaces from the bag!