Lesson Plan
Curated OER

Solving Problems Using Triangle Inequality Theorem

For Teachers 6th
Sixth graders investigate triangles and the inequality theorem. They will collaborate in groups to determine the length of a longest side of a triangle. Then relate the size of the triangle to its angles using protractors, yard sticks,...
Lesson Plan
Curated OER

Triangle Inequality Theorems Investigation

For Teachers 9th - 10th
Young scholars estimate and measure triangles. In this geometry lesson, students identify the relationship between three sides and a triangle. They use the inequality theorem to decide if a triangle will be formed or not.
Lesson Plan
Curated OER

Triangle Inequality Theorem

For Teachers 8th - 10th
Young scholars use the inequality theorem to solve triangles and their properties. In this geometry instructional activity, students are given spaghetti of different lengths and asked to create triangles. They conclude the necessary...
Interactive
CK-12 Foundation

Pythagorean Theorem to Classify Triangles: Missing Angles

For Students 8th - 12th Standards
Learn to use the Pythagorean Theorem with non-right triangles. Pupils use the interactive to discover the relationship between the lengths of sides for acute and obtuse triangles. They compare the squares of the sides of the triangles to...
Lesson Plan
Curated OER

Triangle Inequality Theorem

For Teachers 7th - 9th
Young scholars identify properties of triangles. In this geometry lesson, students create triangles using three different segments. They make conjectures and predictions.
Lesson Plan
Curated OER

Triangles Congruency Theorems

For Teachers 10th
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. 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 angles are formed by...
Lesson Plan
Curated OER

Triangle Sum Theorem

For Teachers 10th
Tenth graders investigate the theorems of angles and lines to prove triagle sum theorem. In this geometry activity, 10th graders discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how...
Lesson Plan
Curated OER

Napolean Triangle

For Teachers 9th - 11th
Learners investigate the Napoleon triangle theory. In this polygon lesson plan, students  differentiate between the boundary points, interior and lattice point of a polygon. They apply concepts of equilateral triangles to solve...
Lesson Plan
Curated OER

Which Triangles are Right

For Teachers 9th - 10th
Students apply properties of right triangles to solve problems. In this geometry lesson plan, students identify axioms and theorems using examples.
Lesson Plan
Curated OER

Exploring the Hinge Theorem

For Teachers 9th - 10th
Students explore the application of Hinge Theorem. In this geometry lesson, students write inequalities, given two sides of a triangle. They solve problems with triangular inequalities using the proper theorem.
Lesson Plan
Curated OER

Triangle Conjectures

For Teachers 10th
Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. 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 angles are formed by...
Printables
Virginia Department of Education

High School Mathematics Geometry Vocabulary Word Wall Cards

For Teachers 9th - 10th
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...
Lesson Plan
Curated OER

Angle-Side Relationships

For Teachers 9th - 12th
Students calculate the different sides and angles of a triangle. In this geometry lesson, students use triangular properties to define the relationship between two triangle. They identify missing angles using the interior angle theorem.
Lesson Plan
Curated OER

Geometric Patterns

For Teachers 7th - 8th
Students explore geometric patterns. Given three straws of various sizes, students conduct tests, and search for patterns, to determine if the various sizes would form a triangle. They use the Triangle Inequality Theorem to determine...
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, students label triangles based on their properties. They find missing sides and angles using the interior sum theorem.
Printables
Virginia Department of Education

Middle School Mathematics Vocabulary Word Wall Cards

For Teachers 5th - 9th
Having a good working knowledge of math vocabulary is so important for learners as they progress through different levels of mathematical learning. Here is 125 pages worth of wonderfully constructed vocabulary and concept review cards....
Lesson Plan
Curated OER

Geometry Jeopardy

For Teachers 9th - 11th
Students identify the pattern in a problem. In this geometry lesson, students make predictions, collect and analyze data. They apply the idea of scales and measurements to the real world.