CER Science Writing Prompt - Geologic Time Scale - Earth ScienceEngage your students in evidence-based scientific writing with this CER (Claim-Evidence-Reasoning) prompt focused on gravitational force and mass—a core concept in middle and high school life science curricula. This ready-to-use resource challenges students to analyze rock strata to determine the Earth’s timeline. Using the CER format, students must construct a scientific explanation to answer the question: "How do rock layers and t