STEM Design Series: No Prep Sub Plans – Solar System: Inner Planets | Scale Model Project (Grades 4–8)Looking for an engaging space + STEM lesson that helps students understand how our closest planetary neighbors compare? In this STEM Design Series: Research + Group Project, students explore Mercury, Venus, Earth, and Mars and design a proportional scale model to show their relative sizes and distances from the Sun. This hands-on challenge builds deep understanding of planetary differences an