Put the vertex in, put the vertex out. Pupils explore theorems about the relationships of lengths of segments and angles of line segments that intersect inside or outside the circle. Learners use the theorems to solve problems involving...

Investigate relationships between angles, arcs, and segments in circles. Pupils use geometry software to discover the relationships between angles, arcs, and segments associated with circles. Class members use similar triangles to...

Here is an engaging lesson which invites learners to cut a strip of adding machine tape that is their height. They decorate their strip, arrange the strips from shortest to longest, and then discuss predictions.

Find the perimeter of squares and rectangles with a straightforward worksheet. An example at the top of the page shows third graders how to find the perimenter, along with the addition problem necessary to find it. Pupils then work on...

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.

Is it a right triangle or not? Introduce scholars to the converse of the Pythagorean Theorem with a lesson plan that also provides a proof by contradiction of the converse. Pupils use the converse to determine whether triangles with...

Discover a new application of the Pythagorean Theorem. Learners prove and apply the converse of the Pythagorean Theorem in the 17th lesson in a 25-part series. The examples ask learners to verify right triangles using the converse...

A bite of bits. The first lesson plan in a unit of 15 introduces the class to the byte. Pupils learn about other standard units for measuring file sizes, develop an understanding of relative sizes and the kind of units used to...

Five questions—multiple-choice, fill in the blank, and discussion—make up an interactive that challenges scholars to mail a teddy bear using the smallest box possible without squishing it. A box with movable sides allows mathematicians...

No fair! I had to run more than they did! Young mathematicians first measure various lengths on a school track. They develop strategies and show calculations to prove that all participants will run the same length using a staggered...

Boat ramps move with waves and changes in water level. Scholars decide on the proper length for a ramp so the angle connecting both sides is appropriate. They visualize the situation and use a simulation to view the results with their...

Get into the swing of things. Pupils use a pendulum to demonstrate the conversion of potential energy to kinetic energy and back. After measuring the speed of a pendulum and compare it to the calculated theoretical speed, they...

What does an MRI machine have to do with a slinky? This activity challenges learners to run a current through a slinky and use a magnetic field sensor to measure the magnetic field. Groups then change the length of the slinky to see...

A six-question interactive tasks mathematicians to solve addition and subtraction problems using front-end estimation. Question types consist of multiple-choice and true or false. A set of wooden beams that can be measured using moveable...

Add some zing to your swing! Explore pendulum motion through an engaging interactive. Physical science scholars specify the pendulum's mass, rod length, and starting angle before they observe the resulting angle graph.

Tell time to the half hour with these analog clocks! The first six problems invite first graders to write the correct times below, while the second set of problems provide the time and empty clock faces. A great way to review your time...

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...

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...

Learners examine objects and find their volumes using geometric formulas in the 21st installment of this 25-part module. Objects take the shape of truncated cones and pyramids, and individuals apply concepts of similar triangles to find...

What happens to the momentum of an object when it strikes another object? Scholars roll a marble down a ramp so it collides with another marble. By measuring the speed of each marble before and after the collision, pupils answer this...

Lead your class on a search for precious bones. Using a presentation, the class investigates the golden ratio in art and nature. Groups of pupils measure specific bones and find the average ratio for the class. To further cement the...

The shortest distance from point A to point B is a straight line—or is it? Young scholars determine the shortest route either along a circular path or through the center of the circle. Learners gain a unique perspective on arc length and...

Sunrise, sunset ... swiftly move the shadows! Pupils practice comparing shadow length data with a hands-on activity. The resource allows users to examine and measure the shadow cast by a stick as the sun moves overhead before testing...

Add a little algebra to the geometry. Class members learn about the Addition Postulate for segments and angles. The pupils use their knowledge of solving equations to find lengths of segments and measures of angles. Individuals apply...