Lesson Plan
Curated OER

Congruent Triangles Postulates

For Teachers 3rd - 4th
Young scholars discover three lettered postulates that prove triangles congruent.
Lesson Plan
Curated OER

Rays and Angles

For Teachers 9th - 12th
Students view examples of a ray, opposite rays, collinear rays, angles, and straight angles. They discuss and demonstrate how to use a protractor and complete worksheet problems on rays and angles.
Assessment
Mathed Up!

Loci and Constructions

For Students 8th - 11th Standards
A General Certificate of Secondary Education math review has class members make basic constructions. Using a protractor and a ruler along with a compass, pupils develop drawings of triangles with given measurements. Scholars use their...
Worksheet
Curated OER

Measuring Angles

For Students 10th
In this measuring angles worksheet, 10th graders solve and complete 8 various types of problems. First, they use a protractor to find the measure of each angle shown. Then, students find the missing angle measures. They also refer to the...
Lesson Plan
Curated OER

Similarity and Congruence

For Teachers 9th - 12th
Students explore the concept of similarity and congruence. In this similarity and congruence instructional activity, students identify and verify whether or not two figures are similar, congruent, or neither. Students use postulates and...
Lesson Plan
Curated OER

Similarity and Congruence

For Teachers 9th - 12th
Students determine that two figures are similar or congruent by investigating figures that are similar and figures that are congruent. They prove that two figures are similar or congruent by using definitions, postulates, and theorems.
Lesson Plan
Curated OER

Angles and Arcs

For Teachers 9th - 10th
Students discuss the sum of central angles and use string to create them on circles. They find the measure and length of both minor and major arcs. Students give examples of concentric, similar, and congruent circles and congruent arcs.
Lesson Plan
Curated OER

Measuring Angles & Segments

For Teachers 10th - 12th
Young scholars view a PowerPoint for a warm-up lesson. They practice measuring around the classroom, measuring such things as the length and width of a desk, pencil, door, and book. Students use a website to practice measuring angles.
Lesson Plan
Curated OER

CSI Investigation of Congruence and Similarity

For Teachers 9th - 12th
Students differentiate between similarity and congruence using polygons. In this geometry lesson plan, students label triangles based on their properties. They find missing sides and angles using the interior sum theorem.
Lesson Plan
Curated OER

Similarity and Congruence

For Teachers 9th - 12th
Learners explore the concept of similarity and congruence. In this similarity and congruence lesson, students cut out strips of paper and form a triangle. Learners try to prove that their triangles are congruent using the SSS theorem of...
Handout
CK-12 Foundation

Ck 12: Geometry: Angles Study Guide

For Students 9th - 10th Standards
This study guide on angles covers key vocabulary, ways to name angles, how to measure them, the Protractor Postulate and the Angle Addition Postulate, types of angles, congruent angles, angle bisectors, and angle pairs. It is available...