Foundations for Success
High school geometry builds on geometry instruction that has occurred throughout elementary and middle school but with the key difference that students must prove and explain concepts they learned about in prior years. In elementary school, students learned about the attributes of shapes, compared and categorized these attributes, and learned to compose and decompose shapes. In middle school, students developed conceptual understanding of angle relationships in parallel line diagrams and angle relationships within and outside of triangles. They have also learned to describe geometric features, measure circumference and area of circles, and make observations and conjectures about geometric shapes using sound reasoning and evidence. Students have learned to “construct” a triangle using different side lengths and that the properties of a triangle are based on the relationship between the side lengths and the interior angle measures. These foundational understandings will be essential to students’ success in this course as they build chains of reasoning to explain, model and prove geometric relationships and situations.