The Children's Center at Caltech has been providing STEM-focused early childhood education for over 16 years. Recently, they have focused more on the "E" for engineering. They created engineering challenges and scenarios for different age groups to explore. For infants, they explored clay and used tools and their bodies. Toddlers experimented with catapults and building structures. Preschoolers designed boats out of foil. Through these activities, the children demonstrated natural engineering behaviors like asking questions, imagining, creating, designing, testing and improving. The Center documented the children's experiences and wants to share them with parents to help parents understand appropriate engineering for young children.