Every set builds 6 working models. Set 1 (Forces & Light): magnetic levitation pen, wind glider, balancing robot, fiber-optic light, 3-ball space orbit and hydraulic loader. Set 2 (Power & Motors): hand-crank generator, electric motor, electric pumping unit, conductor detector, periscope and Newton's cradle. Set 3 (Machines & Robots): Dutch windmill, fighter jet, hydraulic lifting platform, hand-cranked crane, spider robot and automatic serving machine.

You get Sets 1 and 2 (12 projects, each in its own bag) plus a printable countdown pack, emailed after you order. Print the pack, tape a Day 1–12 tag on each project bag, and hang the countdown poster. Each day your child opens one bag, builds it, and reads that day's science card. We suggest starting December 13 so the last build lands on Christmas Eve, but it works for any 12 days, including the holiday break after Christmas.

Every order ships with tracking. Processing takes 7–10 business days, and we'll email your tracking number as soon as it ships. Planning a 12 Days of STEM countdown? Order by November 16 to start on December 13. Giving it as a Christmas gift? Order by December 1 for delivery before Christmas. If you need help with your order or a return, our team is here to make it right.

All pieces are laser-cut wood with smooth, sanded edges, and the kits are designed for ages 8–12. The parts are small and some are delicate, so fit them gently and take your time. Younger brothers and sisters should only build with an adult.

Older kids can often follow the step-by-step guides on their own. Younger builders (around 8–9) usually want an adult nearby, especially for connecting the small wires on the electric models. Some models need batteries, so check each project's guide and have them on hand before you start. If a part is ever missing or broken, contact our team and we'll make it right.