LEARN NC

K–12 teaching and learning · from the UNC School of Education

Goal 2

Geometry and Measurement - The learner will use geometric and algebraic properties of figures to solve problems and write proofs.

Objective 2.03

Apply properties, definitions, and theorems of two-dimensional figures to solve problems and write proofs:

  • Triangles.
  • Quadrilaterals.
  • Other polygons.
  • Circles

Resources aligned to this objective

Proof Puzzles
Students will work in small groups to put geometric proofs that have been cut apart in the correct order. They will organize statements with the correct reason. A recorder in the group will write the finished product for the group to turn in to the teacher.
Format: lesson plan (grade 9–12 Mathematics)
By ann mewborn.

Lesson plans on the web

Mathematical proofs
Students explore the nature of mathematical proofs and mathematical inquiry. (Learn more)
Format: lesson plan (grade 8–12 Mathematics)
Provider: American Association for the Advancement of Science
Reflect on this
In this lesson, from Illuminations, students investigate reflections in a plane using mirrors (or other reflective materials) and a geometry utility. They apply their findings to examination of interior angles of regular polygons. (Learn more)
Format: lesson plan (grade 9–12 Mathematics)
Provider: National Council of Teachers of Mathematics
Symmetries I: Conclusions
This lesson challenges students to reflect on the mathematical ideas learned in a multi-part lesson on Geometry. (Learn more)
Format: lesson plan (grade 9 Mathematics)
Provider: National Council of Teachers of Mathematics