Teach your class how to solve problems using the triangle sum theorem. For this geometry lesson, high schoolers identify the missing angles in a triangle using the sum theorem. They graph triangles on the TI and moves the sides around to...

Pupils investigate similar triangles and proportions as they make conjectures about the length of sides of similar triangles. For this lesson, have your class construct similar triangles using Cabri Jr so that they share a common vertex.

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 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.

Young mathematicians draw and label right triangles using Cabri Jr. technology. They create other special right triangles and identify the length of the hypotenuse and each leg. High schoolers explore the ratios to determine how the...

High schoolers explore the concept of quadrilaterals as they find the midsegments of quadrilaterals using Cabri Jr. on a graphing calculator. They find midpoints, slopes, angles, and distances of lines and angles.

Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts...

Circles are the foundation of many geometric concepts and extensions - a point that is thoroughly driven home in this extensive unit. Fundamental properties of circles are investigated (including sector area, angle measure, and...

Gaining practice in translating a verbal description into a diagram and then an equation is the real point of this similar triangles exercise. Once the diagram is drawn, multiple methods are provided to reach the conclusion. An effective...

Students investigate the Pythagorean Theorem. In this geometry lesson, students define angles and sides of right triangles. They calculate the area and surface area using formulas derived by the Pythagorean Theorem.

Seventh graders develop strategies for finding the perimeter and area of large geometric figures. Through lecture and guided practice, 7th graders practice the strategy of dividing a geometric shape into smaller more manageable shapes...

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

In this geometry worksheet, 10th graders calculate the perimeter and area using the specific formula for that polygon. There are 5 questions with an answer key.

Students calculate the area of triangles using a variety of materials including computer applets.

Students familiarize themselves with the construct and measure menus. They demonstrate how to use the Sketchpad Calculator. They draw a triangle and construct the centroid. They shade in each of the small triangles and measure the area.

What does popcorn have to do with math?  Seventh grade mathematicians are provided an opportunity to develop a conceptual understanding of the formula for volume and to use it as a tool to solve problems. The lesson begins with a...

Sixth graders identify and use area formulas for finding the area of geometric shapes.

Add up areas of squares to discover the pythagorean relationship. Small groups create right triangles with squares along each side. They calculate the areas of each square and notice the relationship. Groups construct other types of...

Many things in life take the shape of a polynomial curve. Learners design a polynomial function to model a riverbed. Using different strategies, they find the flow rate through the river.

The history of math is fascinating! Utilize a woodcut primary source image from 1492 and posters from the 1930s to help geometers apply their volume-calculation skills to real-life questions. 

Learners analyze characteristics and properties of two- and three-dimensional geometric shapes and develop mathematical arguments about geometric relationship

For this geometry worksheet, students differentiate between isosceles and regular triangles. They calculate the area and perimeter of the triangle. There are eleven questions with an answer key.

Students find the perimeter and area of circles, triangles, and rectangles. In this perimeter and area lesson plan, the teacher gives students formulas for each shape and measurement and works through examples on the board. While no...

Students calculate the determinant. In this algebra lesson, students find the determinant and use to calculate the area of a triangle. They calculate the area of a quadrilateral in a plane.