The key to understanding is making connections. Scholars explore angle dilations using properties of parallel lines. At completion, pupils prove that angles of a dilation preserve their original measure. 

Determine the level of understanding within your classes using a summative assessment. As the final lesson in a 29-part module, the goal is to assess the topics addressed during the unit. Concepts range from linear angle relationships,...

Provide your emerging mathematicians with the tools to learn as they incorporate auxiliary lines to solve unknown angle proofs in this continuing segment. They decipher information from a diagram to uncover the missing pieces and...

Can they put it all together? Ninth graders apply what they know about proofs and triangle congruence to complete these proofs. These proofs go beyond the basic triangle congruence proofs and use various properties, theorems, and...

Is that drawn to scale? Capture the artistry of geometry using the ratio method to create dilations. Mathematicians use a center and ratio to create a scaled drawing. They then use a ruler and protractor to verify measurements. 

Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems. 

Using a similar process from the first instructional activity 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...

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. 

Amaze your classes with the ability to find side lengths of triangles immediately — they'll all want to know your trick! Learners use the Pythagorean Theorem and special right triangle relationships to find missing side lengths.

Review the principles of scaling areas and draws a comparison to scaling volumes with a third dimensional measurement. The exercises continue with what happens to the volume if the dimensions are not multiplied by the same...

This one activity requires young geometers to pull together information they are currently learning with things they have learned previously. Here they rely on understanding something about parallel lines, alternative interior angles,...

What time is it when the arc length is pi? An interactive displays the measure of the angle created between the hour and minute hand of a clock. Pupils can set the clock to different hours and calculate the arc length based upon the radius.

Swimming is more fun with quantities. The short assessment task encompasses finding the volume of a trapezoidal prism using an understanding of quantities. Individuals make a connection to the rate of which the pool is filled with a...

In this 2-D shapes lesson, kindergarteners review plane shapes attributes. They engage in a shape hunt in the classroom and create art using plane shapes. A good, hands-on lesson!

Parallel lines seem so right for each other. It's too bad they'll never, ever meet. Learners use tracing paper to discover relationships among angles formed by two parallel lines cut by a transversal. They apply this information to find...

A benthic habitat hosts a vast collection of organisms and its structure influences the biodiversity. Middle-school marine biology explorers will discuss how corals impact structure, and therefore diversity, on the ocean floor. They draw...

Shapes are so fun! Little ones explore, identify, and create shapes using tangrams or pattern blocks. The activity is intended to stimulate critical thinking while engaging learners through play and shape identification. Each child will...

Given a pair of parallel lines and a triangle in between, geometers prove that the sum of the interior angles is 180 degrees. This quick quest can be used as a pop quiz or exit ticket for your geometry class.

Review guide, practice test, homework packet? Yes, yes, and yes as it's all possible with a wonderful trigonometry packet. Every type of problem is there, starting from the unit circle and ending with conic sections. 

A quadrilateral is drawn on the coordinate plane, and eighth grade geometers find the length of each side and the diagonals by applying the Pythagorean theorem. 

Having a good working knowledge of math vocabulary is so important for learners as they progress through different levels of mathematical learning. Here is 125 pages worth of wonderfully constructed vocabulary and concept review cards....

Provide your class some practice with the dimensions of geometric figures. Here you have a set of three different-shaped, stemmed drinking glasses with diameters and heights provided. Math-minded individuals calculate the volume of each....

An excellent way to reinforce math vocabulary in your classroom! Seventy-eight posters focus on number and number sense, computation and estimation, measurement, geometry, probability and statistics, and patterns, functions, and algebra.

Students explore symmetry.  For this geometry and scientific inquiry lesson, students design paper airplanes with middle line symmetry, as well as right, obtuse, and acute angles.  Students measure the plane's angles using a...