Curated OER
Proof of the Pythagorean Theorem Using Transformations
Middle and high schoolers construct a triangle using Cabri Jr. They construct squares on each of the legs and hypotenuse of the triangle. Pupils show that the area of the squares on the leg equal the area of the square on the hypotenuse.
Curated OER
Exploring the Circumcenter of a Triangle
Students construct the circumcenter of a triangle. In this constructing the circumcenter of a triangle lesson plan, students construct a triangle using Cabri Jr. Students draw perpendicular bisectors of the sides of the triangle....
Curated OER
Congruent Triangles
Students identify properties of triangles. In this geometry lesson, students differentiate between similar and congruent triangles. They use the umber of sides to help define the angle of the polygon.
Curated OER
Triangles
In this triangles instructional activity, 10th graders solve 3 extensive informal geometry problems that involve triangles. First, they sketch a triangle, selecting 3 of the sides and constructing 3 midpoints. Students then draw each of...
Curated OER
Ratios in Right Triangles
Learners calculate the sides of right triangles in this trigonometric ratios lesson. They use Cabri Jr. software and TI-83 or TI-84 calculators to find the side lengths and their ratios to each other for various triangles. The provided...
Curated OER
Triangle Congruence
Students use web applet to create congruent triangles. In this geometry lesson, students differentiate between congruent and similar. They create shapes online and drag those shapes around to create visuals of triangles.
Curated OER
Special Right Triangles
Students identify different types of special right triangles. In this geometry lesson, students differentiate between right triangles and isosceles triangles. they construct the triangles using geometry software and make conjectures...
Curated OER
Identifying Similar Triangles
In this identifying similar triangles activity, 10th graders solve 6 different types of problem that include identifying and comparing similar triangles. First, they identify the three ways that determine whether two triangles are...
Curated OER
Triangle Classification
High schoolers classify different types of triangles. In this geometry lesson, students identify and use properties of triangles. They differentiate between isosceles and equilateral triangles.
Curated OER
Nested Similar Triangles
Nested triangles have been created so that they share a common vertex and vertex angle. Learners drag the endpoints of the side that is opposite the common angle to discover the conditions that make the nested triangles similar. When...
Centre for Education in Mathematics and Computing
Roots and the Pythagorean Theorem
In this roots and the Pythagorean Theorem learning exercise, learners solve 15 different types of problems related to square roots and applying the Pythagorean Theorem. They first determine the square root of each number and then, the...
Curated OER
Triangle Sum Theorem
Teach your class how to solve problems using the triangle sum theorem. In this geometry lesson, students identify the missing angles in a triangle using the sum theorem. They graph triangles on the TI and moves the sides around to create...
Curated OER
Circumscribing a Circle About a Triangle
Pupils circumscribe a circle about a triangle. They construct a triangle using Cabri Jr and then circumscribe it. They then use knowledge of perpendicular bisectors and circumcenters to locate the center of the circle and then...
Curated OER
Investigating Segments in a Right Triangle
High schoolers explore the concept of right triangles as they construct a right triangle using Cabri Jr. Learners find the midpoint of the hypotenuse and construct a line from the midpoint to the vertex of the right angle. They then...
Curated OER
Investigating Segments in a Triangle
Pupils investigate segments in a triangle by constructing a triangle using Cabri Jr. They construct segments within the triangle that lie on the midpoints of the triangle's sides. Learners then compare the slope of base of the triangle...
Curated OER
Measuring Angles in a Triangle
High schoolers investigate the sum of the measures of the angles of a triangle. They draw a triangle and measure the interior angles. Using Cabri Jr., learners find the sum of the measures of the interior angles. The lesson provides an...
Curated OER
Types by Texture: Soil Isn't a Dirty Word
Second graders experiment with different types of soil to find the texture. For this types of soil experiment, shake a jar of soil and water and record the settling of the soil. Students record again after 3-4 hours and note the level...
Curated OER
Area of Shapes
In this area of shapes worksheet, students determine the area of equilateral triangles, acute triangles, and compound figures. This one-page worksheet contains 3 multi-step problems. Answers are provided with this interactive...
Concord Consortium
Always, Sometimes, Never
Do your learners always, sometimes, or never remember the properties of the segments in triangles? Get that number closer to always with a creative lesson analyzing all four segments. Scholars consider a statement about one of the...
Curated OER
Geometry Level 3
What a wonderful resource! Learners create two-dimensional shapes according to the instructions stated, use the squares to make a triangular prism, a cube, and a pyramid, and identify features of plane shapes, among a myriad of other...
Curated OER
Identifying Triangles
Sixth graders identify and define a variety of triangles. In this identification of triangles instructional activity, 6th graders draw examples of each triangle on a whiteboard, then complete a worksheet.
Curated OER
Counting Triangles
Sixth graders examine triangles in a figure. In this geometry lesson plan, 6th graders establish a method for counting triangles within a given figure. Students discover that the total number of triangles is the sum of all numbers counted.
Curated OER
Triangles and Things
Young learners listen to the story book The Greedy Triangle as the teacher introduces new polygon shapes. They use geometric stencils to trace a quadrilateral, a pentagon, a hexagon, and an octogon onto a foldable notepad....
Curated OER
Draw 3 Dimensional Objects
Bring three-dimensional shapes to life in your classroom. First introduce the vocabulary of three-dimensional shapes, such as sphere, cube, and pyramid. Then, show your kids examples of how to use two-dimensional objects draw...