This 108-piece STEM building set allows children to construct their own engineering creations, including twisting and turning Treadmobiles. The set includes an Activity Guide with step-by-step building instructions. Each build encourages the development of engineering, critical thinking, and other STEM-related skills. The pieces are compatible with all Gears! Gears! Gears! building sets for expanded play possibilities. Suitable for gifting on various occasions, including holidays, birthdays, or as an educational supplement for homeschooling.