All Ages | $15 per girl | $4 per adult | Children 5 and under FREE
Joliet Gathering Place, 1551 Spencer Road, Joliet, IL 60433

Custom patch and T-shirt included with registration!

• Daisy Derby (Grades K–1) | Saturday, May 4, 10 a.m.–12 p.m. »
• Brownie Derby (Grades 2–3) | Saturday, May 4, 1–3 p.m. »
• Junior Derby (Grades 4–5) |Sunday, May 5, 10 a.m.–12 p.m. »
• Cadette, Senior, and Ambassador Derby (Grades 6-12) | Sunday, May 5, 1–3 p.m. »

Join us for the 5th Annual Girl Scouts of Greater Chicago and Northwest Indiana Turbo Trefoils Derby at the Joliet Gathering Place.

Join us to work on your car at the Derby Build Day on April 27! Bring your derby car kit and ideas. We’ll have tools and paint so you can work on your derby car, then test it at our aerodynamic testing station! Pizza will be provided. Sign up now!

How to Compete in the Trefoil Derby

This is your chance to design your own trefoil derby car with your troop, friends, or family, then race your car against other Girl Scouts in your age group!

Purchase your official Trefoil Derby Car Kit. Kits come with an official race pass, and must be purchased through a GSGCNWI shop (we have them in stores and online!). Any cars purchased at other locations will not be qualified to race. Purchase now »

Get to work on your car, and be sure to follow Official Derby Rules!

2019 Official Derby Rules

Upon arrival we will weigh each car with the “official scale” and turn back any car that exceeds 5.0 oz.

We will then do a quick visual inspection of each car against the following inspection points:

Car Dimension Rules

• The overall length of the car shall not exceed 7 inches.
• The overall width of the car shall not exceed 2 ¾ inches.
• The car must have 1 ¾” clearance between the wheels.
• The car must have 3/8” clearance underneath the body so it does not rub on the track.

Derby Car Weight Rules

• The car shall not exceed 5.0 ounces.
• The official race scale that is used at car check-in shall be considered final.

Car Modifications Not Allowed

• The official wood block must be used. The block may be shaped in any way that is desired.
• The wheel may not be changed from the original wheels sold with the kit. The track is set to exact dimensions of the original wheels.
• The wheels may not be cut, drilled, beveled or rounded. You may remove the seams and imperfections from the wheels that result from the plastic mold formation process.
• The axles may be polished and lubricated, but you must use the axels that come with the kit.
• Axels must be placed in the precut slots on the wooden block, you may not move them forward or back on the car.

Other Derby Race Rules

• Once a car passes inspection and is entered into the race, only race committee members can touch it.
• If the car loses a wheel, or is otherwise damaged, the racer shall have 5 minutes to make repairs.
• Each car must pass inspection by the official inspection committee before it will be allowed to compete. The Inspection Committee has the responsibility to give a time penalty to (0.50 sec.) those cars that do not meet these rules.

Are Pinewood Pro parts allowed?

• As long as the car passes the guidelines explained above without any violations the car will be allowed to race.

Are Pinewood Pro Wheels and Axles Legal?

• Graphite-coatings on axles and wheels are legal.
• You must use the original wheels sold with the kit and car must conform to dimension guidelines.

Information about Derby day will be sent to those who are registered via email one week prior to the event.