@Weezilou Yes, the boys design and do as much work as they are able to do. By the time my boys were Webelos (age 9 and 10), they were able to do a lot of the work themselves, except work with power tools.
@cscarr97 My boys always loved Pinewood Derby. They took a couple of their old cars to run as testers on track! LOL! They loved doing pinewood derby. They had fun cheering on the Cub Scouts and helping run the event.