Help young learners explore waterproof materials, engineering design, and school book care with these Library Book Rain Shield STEM Challenge Worksheets: Design a Waterproof Cover K–2. This low-prep printable STEM resource helps Kindergarten, 1st Grade, and 2nd Grade students identify a real rainy-day problem, observe material test results, count water drops kept out, choose design criteria, plan a protective cover, record test evidence, compare solutions, and improve a prototype. Instead of com