O.K. first you have to get footage of the competition,next no need to worry about aerodynamics the cars don't get going fast enough for that to come into play weight is the most important thing,check the official rules as some don't allow the use of the precut kits you get at the hobby stores. just have fun .I felt really bad building my sons pinewood derby car all by myself, but hey I .... We won. Just kidding ,well not really, it's not about winning so come up with a cool design as that's what I remember from my scouting days was the cool styling that showed up especially that metallic blue streamlined job. good luck