The Geometry course builds on Algebra 1 by extending students’ ability to see geometric relationships and to see how those geometric relationships are often alternate representations of the relationships they studied in the previous year. Students develop an approach to analyzing geometric relationships and explaining their reasoning logically and precisely, eventually leading to proof (informal and formal).
The major concepts identified for the geometry course are congruence, similarity, right triangles, trigonometry, using coordinates to prove simple geometric theorems algebraically, and applying geometric concepts in modeling situations. The figures that are used to communicate around these relationships and representations build from the notions of point and line into polygons and circles.
The process of articulating sound and precise reasoning is threaded throughout the geometry course. Therefore, reasoning and sense making should be a regular part of instruction, with or without formal proof writing. Integration of the Common Core Standards for Mathematical Practice will be critical for students understanding of how to approach Geometry. Through “practicing” reasoning, students will be progressing toward expressing course-level appropriate geometric thinking by constructing viable arguments, critiquing the reasoning of others and attending to precision when making mathematical statements.