So many times the characteristics of triangles are presented as a vocabulary-type of lesson, but in this activity they are key to unraveling a proof. A unique attack on proving that an inscribed angle that subtends a diameter must be a...

Learn about constructing figures, proofs, and transformations. The seventh unit in a course of nine makes the connections between geometric constructions, congruence, and proofs. Scholars learn to construct special quadrilaterals,...

Young mathematicians build an understanding of area and perimeter with their own two hands in a series of interactive geometry lessons. Through the use of different math manipulatives, children investigate the properties of...

A General Certificate of Secondary Education math review has class members make basic constructions. Using a protractor and a ruler along with a compass, pupils develop drawings of triangles with given measurements. Scholars use their...

Trace the links between a variety of math concepts in this far-reaching unit. Ideas that seem very different on the outset (like the distance formula and rigid transformations) come together in very natural and logical ways. This...

How many sides does that polygon have? Building directly from lesson number eight in this series, learners now find the area and perimeter of any polygon on the coordinate plane. They decompose the polygons into triangles and use Green's...

How does the number of sides of a polygon affect the angle measures? Learners recognize a pattern in finding the total measure of interior and exterior angles and the number of diagonals. They use the patterns to calculate...

Learners follow a series of instructions for drawing and coloring different shapes in order to learn the difference between the perimeter and area of a polygon. Then they are asked to find the perimeter and area of a 3x4 rectangular...

More than just a worksheet, the resource provides a thorough guide to navigate through the land of parallelograms. Filled with definitions and theorems, the resource supports learners through problems such as proofs and finding missing...

Geometry could be called the study of figures. An overview of the figures found in a typical geometry course contains a study of different triangles, quadrilaterals, and regular polygons. 

Challenge the class with inscribed circles in triangles. The assessment task requests class members use their knowledge of circles and right triangles to prove two triangles are congruent. They go on to utilize their knowledge of...

All shapes have certain defining attributes that set them apart from others. In order to understand this, young mathematicians look at examples and non-examples of triangles, rectangles, and squares, working as a whole class to create...

This short video show viewers how to connect the sum of the angles in a triangle to other angle measurements. Pupils determine the missing measures for angles involved with triangles and quadrilaterals. Class members then must explain...

When algebra and geometry get together, good things happen! Given a system of inequalities that create a quadrilateral, learners graph and find vertices. They then use the vertices and Green's Theorem to find the area and perimeter of...

Just what does it take to show two rhombuses are similar? The assessment task asks pupils to develop an argument to show that given quadrilaterals are rhombuses. Class members also use their knowledge of similar triangles to show two...

Everyone knows that opposite sides of a parallelogram are congruent, but can you prove it? Challenge pupils to use triangle congruence to prove properties of quadrilaterals. Learners complete formal two-column proofs before moving on to...

Identify shapes based on their attributes. Second graders are tasked to color triangles, quadrilaterals, pentagons, and hexagons specific colors. The one thing these shapes have in common? They are all polygons.

Test your scholars' knowledge of a multitude of concepts with an assessment aligned to the California math standards. Using the exam, class members show what they know about the four operations, positive and negative numbers, statistics...

Acute angles, nets, and vertices are only a few terms that a set of flash cards includes. Among the 108 cards, two types are available; word cards printed in bold-faced lettering, and corresponding definition cards equipped with an...

In this understanding triangles instructional activity, students read 6 pages of examples and explanations about identifying triangles, determining length of sides and degrees of angles, including the hypotenuse, then answer 28...

For this area of polygons activity, 9th graders solve two area of rectangles, one area of parallelogram, and ten area of triangles problems.  The formulas for finding the area of these figures are provided.

Your geometry learners use their knowledge of various geometric concepts to write proofs. Starting with givens containing parallel line segments with transversals and triangles and quadrilaterals, and the mid-point and distance formulas;...

Your learners get extra practice using coordinates in calculating mid points, finding end points, deciding if points are collinear, calculations using slope concepts, writing linear equations, using triangles and quadrilaterals, and...

Add some visual support to your elementary geometry lessons with this set of printable shape cards. From triangles and squares to octagons and nanogons, this simple resource can be used in countless ways to develop children's knowledge...