This physical science lesson focuses on describing the Law of Conservation of Matter. The lesson includes research-based strategies and strategic questions that prepare students for assessments. In this lesson, students read a balanced chemical reaction and draw a molecular model for the reactants and the products. Then, students count and write the number of atoms for the reactants and the products. Finally, students read passages and complete a graphic organizer, as well as explaining why a chemical reaction does or does not obey the Laws of Conservation of Matter. In addition to the lesson, there are four pages for Independent Practice and review modeled after current adaptive testing items.