My boys pick their design and sketch it on the wood. I fine tune their design for them. I rough cut the design. I hold the orbital sander face up while they finish sand their car to the form or shape they want. They always ask me to help at the end so they hold the sander while I shape the car. I drill out the new axle holes (nothing fun or cool about that for them). They pick the paint. I show them spray paint technique and let them go at it. They inevitably ask me to help. They pound the axles straight with the jig and hammer. I inspect and tap here and there where needed. I chuck the axles and run the drill while they polish with sand paper, etc. I chuck the wheels and run the drill while they polish the wheels with sand paper, etc. I add weight to the car. I install the wheels and axles. They lube the axles.

My kids have always placed in the top 3 and have one a couple of times. They feel they are completely involved in making the car because they are. I oversee and ensure alignment, polishing, lubing, and weight distribution, etc. - aspects that are performance related. As my boys neared the end of their cub experience, they did more and more of the performance-related functions.

It's a win-win for the two of us and hopefully a third win at the finish line.