Students estimate and measure triangles. In this geometry instructional activity, 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.

Not all triangles are created equal. A simple hands-on activity has learners investigate the side lengths of triangles. They use pipe cleaners to determine whether triangles of given side lengths can exist and then use the results to...

High schoolers investigate the relationship between angle measures and sides of a triangle and the relationships among the three sides of a triangle. The use of technology (Cabri, Jr.) allows learners to make and test conjectures as they...

Students 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 length...

Students identify properties of triangles. In this geometry instructional activity, students create triangles using three different segments. They make conjectures and predictions.

Students draw a chart (included in the lesson) to use with their investigation. They review terminology of triangles and receive toothpicks to use in the lesson. Beginning with three toothpicks, students form a triangle. They complete...

What did the triangle say to the circle? You're pointless! Class members will get the point when they investigate relationships between side lengths of a triangle using the Triangle Inequality Theorem. Pupils then create an...

High schoolers explore the concept of triangle inequalities.  In this triangle inequality lesson, students cut spaghetti noodles into given lengths.  High schoolers use the noodles to complete a worksheet about triangle...

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...

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...

Students investigate the Napoleon triangle theory. In this polygon instructional activity, students  differentiate between the boundary points, interior and lattice point of a polygon. They apply concepts of equilateral...

Students apply properties of right triangles to solve problems. In this geometry lesson plan, students identify axioms and theorems using examples.

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.

Tenth graders investigate the theorems of ASA, AAS, AAA and ASA. In this geometry lesson plan, 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...

Learners 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.

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.

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.