Learners investigate properties of similar figures. For this properties of similar figures lesson, pupils construct similar figures using Cabri Jr. They dilate their figure to create a similar one, and discuss the relationships between...

Scholars can use area formulas, but can they apply what they know about area? The lesson plan challenges learners to think logically while practicing finding area of shapes such as rectangles, circles, parallelograms, triangles, and...

As they investigate scaling figures and calculate the resulting areas, groups determine the area of similar figures. They continue to investigate the results when the vertical and horizontal scales are not equal. 

Using a similar process from the first lesson in the series of finding area approximations, a measurement resource develops the proof of the area of a circle. The problem set contains a derivation of the proof of the circumference...

Your class will use a TI calculator to drag vertices of rectangles and triangles to observe what happens to ratios of pairs of sides within each figure. They will apply the definition of similarity to identify similar shapes. The lesson...

Students identify the ratios of different triangles. In this geometry lesson, students identify the similarity and differences of triangles. They use the navigator to move the sides of the triangle around.

Explore finding the surface area of composite figures. Building on the previous lessons in the 29-part series, the 24th installment examines the surface area of three-dimensional solids. The focus is on decomposing composite figures and...

Students determine the relationship between perimeter, circumference, area, surface area, and/or volume of similar figures and their parts. They complete activities related to the question. Answer key included.

Learners of all ages investigate area and perimeter through pentominoes. For this geometry lesson, students calculate the are and perimeter of different geometric shapes and describe the properties of similar and congruent shapes. This...

Investigate perimeter and area of polygons! In this measurement lesson, learners use index cards to create rectangles and trace their hand to estimate its area and perimeter.

Students explore the relationships between similar figures. In this relationships between similar figures lesson, students discuss relationships between perimeter, circumference, area, surface area, and volume of similar figures through...

An excellent lesson that encourages students to discover how complex figures can be broken into simpler shapes when measuring area. Working with block letters, learners are given the freedom to develop their own strategies for...

Learners explore scale factor as they create a scale drawing of a box, then determine the surface area and volume of the original and the scale drawing. The one page worksheet contains activities and procedures with four questions....

Sixth graders explore characteristics of similar objects. Using attribute blocks, they explore the ratios of the perimeter, area and side length in similar shapes. They calculate and compare the area of shapes.

Puzzle your way through to a new understanding of area. Scholars learn about the area of polygons through equidecomposability, the idea that polygons that can be decomposed into the same set of pieces have the same area. By using...

Lead a discussion on the similarities between the properties of area and the properties of volume. Using upper and lower approximations, pupils arrive at the formula for the volume of a general cylinder. 

Double the dimensions, quadruple the surface area. Pairs build similar prisms and compare the ratios of their surface areas and volumes to the ratio of the heights. Given two similar cones, partners determine the ratios of the lateral...

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.

Students explore similar figures. For this surface area and volume lesson, students identify the relationship between the surface area and volume of similar figures.

Learners calculate the perimeter and area of given figures and lengths.

Build upon the Pythagorean Theorem with the Law of Cosines. The 10th part of a 16-part series introduces the Law of Cosines. Class members use the the geometric representation of the Pythagorean Theorem to develop a proof of the Law of...

Students find the factor of proportionality in similar polygons. In this similarity of polygons lesson plan, students measure the sides and angles of polygons and derive a factor of proportionality between corresponding pairs of sides...

Here is a lesson that has learners take a look at corresponding parts of similar triangles, ratios of similarity, reductions and enlargements. They'll manipulate the scale factor (r) to observe the changes in similar triangles and then...

Students identify the volume of cones and pyramids. In this geometry lesson, students derive the formula for cones and pyramids. They calculate the volume of cones and other three dimensional shapes.