The raingutter regatta is a boat race in which cub scouts construct a simple sail boat. The boats are raced along a narrow channel. The boats are blown down the channel. Assembly kits are supplied by the pack.

Raingutter Regatta rules

The pinewood derby is a parent-son project to build a race
car made from a block of pinewood. The car must weigh 5 ounces or less. The cars are powered by gravity and run down a regulation track. The pinewood derby is an annual event for most packs. It can be run indoors or outdoors. Assembly kits are supplied by the pack.

Pinewood Derby rules

Each den works together to build a "Cubmobile," a gravity-powered racing vehicle. Younger dens may already have previously built racers assigned to them. Each den has one racer, and each boy in the den has the opportunity to race the car. A ramp is used to help start the cars, and they are gravity-propelled downhill to the finish line. The race is held on a smooth street with a gradual slope, in cooperation with local authorities.

Cubmobile Derby rules                                 Cubmobile design plan

A popular family-son project is the space derby. It's similar to the pinewood derby except the models are miniature rockets driven by propellers powered by rubber bands along a suspended, heavy monofilament line. Assembly kits are supplied by the pack.

Spaceship Derby rules