The Pythagorean Theorem is a staple of middle school geometry. Scholars first investigate angle relationships, both in triangles and in parallel lines with a transversal, before proving and applying the Pythagorean Theorem.

Learners discuss and review examples of the Pythagorean Theorem using a GSP, Geometer's Sketchpad, activity.

Students identify triangles as similar or congruent. In this geometry activity, students drag triangles around on the navigator to see the effect of different angles on the shape of the triangle. They discuss angle similarity and angle...

Your learners connect the new concepts of transformations in the coordinate plane to their previous knowledge using the solid vocabulary development in this unit. Like a foreign language, mathematics has its own set of vocabulary terms...

Use the parallel lines to find your way. After first reviewing geometric constructions and the relationships between angles formed by parallel lines and a transversal, young mathematicians write proofs for theorems relating to parallel...

Given a diagram of connected or overlapping triangles, individuals must find congruent parts using various properties. Pictures include reflexive sides and vertical angles amongst the marked congruent parts.

Students use the inequality theorem to solve triangles and their properties. For this geometry lesson, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary length needed to make a...

Tenth graders investigate the theorems of angles and lines to prove triagle sum theorem. In this geometry lesson, 10th graders discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two...

Tenth graders investigate parallel lines and their special angles cut by a transversal. In this geometry lesson plan, 10th graders identify and find corresponding, alternate interior, and alternate exterior angles formed when parallel...

Having a good working knowledge of math vocabulary is especially important for geometry learners. Here are 119 pages worth of wonderfully constructed definitions, constructions, formulas, properties, theorems, and postulates. This is a...

Students explore the application of Hinge Theorem. In this geometry instructional activity, students write inequalities, given two sides of a triangle. They solve problems with triangular inequalities using the proper theorem.

Congratulations, you've just hit the word problem jackpot! Covering an incredible range of topics from integers and fractions, to percents, geometry, and much more, this collection of worksheets will keep young mathematicians...

The problem seems simple: find the area of the equilateral triangle whose sides are each length 1. In fact, this same problem is solved in 8th grade, addressing a different Common Core standard, using the formula for area of a triangle...

Students differentiate between similar and congruent polygons. For this geometry lesson, students define the theorems and reasons for polygons similarity and congruence. They are given pictures and patterns to differentiate and identify.

Learners differentiate between similar and congruent triangles. In this geometry lesson, students identify the angles of triangles using the similarity theorem. They apply concepts of triangles to the real world.

Students draw diagrams demonstrating how it is possible to two central angles to be congruent and their minor arcs are not congruent. In groups, they illustrate theorems with their constructed circles, create diameters of circles that...

Students are introduced to the basic trigonometric identities. Using a diagram, they discover why the parts of the unit circle as named as they are and use equations to finalize the Pythagorean trigonometric identities. They also review...

This task asks learners to prove that the segment joining the midpoints of two sides of a parallelogram is both congruent and parallel to an adjacent side of the parallelogram. The activity would be good to use in a discussion about how...

Students investigate triangles and congruences. In this geometry lesson plan, students differentiate between inductive and deductive reasoning. They differentiate between similar and congruent triangles.