Children are natural engineers. Engineering design activities for preschoolers introduce practices and encourage scientific habits of mind. The "Next Generation Science Standards" (NGSS Lead States 2013) highlight that crosscutting concepts and disciplinary core ideas can not be mastered without engaging in scientific investigations and engineering practices. In light of this, the authors designed a series of activities, that are presented in this article, to introduce engineering practices and the engineering design process to preschool-age children. In this unit, the authors focus on engineering design as the main disciplinary core idea and chose Structure and Function as their main crosscutting concept. They heavily rely on the engineering design process and science and engineering practices to provide an opportunity for students to engage in authentic real-world applications. This series of activities is supported by the National Science Teachers Association's (NSTA's) key principles that guide science learning among young children. Specifically, that: (1) Children have the capacity to engage in scientific practices and develop understanding at a conceptual level; (2) Young children need multiple and varied opportunities to engage in science exploration and discovery; and (3) Young children develop science skills by engaging in experiential learning.