This STEM BUNDLE is designed for Pre-School learners using the letters from A-D. Each of the Units involves STEM Challenges and excellent easy to use activities for HOME-SCHOOL parents! Having used these units in both Pre-School settings and in local library classes, I know that these lessons work well as EDUCATIONAL and FUN activities. I like to encourage each child's curiosity with HANDS-ON materials. My focus is the scientific method and the Next Generation Science Standards.