New ReviewMark off the length of the radius around the circle. Using a compass, the presenter shows how to construct a regular hexagon in a circle. Pupils see how triangles formed in the hexagon are equilateral, allowing for the construction to...

New ReviewSometimes it's how you ask the question that counts. The sixth installment of nine from the Smarter Balanced Claim 1 Slideshow series presents a set of 13 questions to assess understanding of angle relationships as well as area and...

New ReviewUnravel the mystery behind the infamous number pi. Scholars complete a series of activities that explores where pi comes from, its digits and estimation strategies. Pupils should be ready to measure, calculate, and look for patterns to...

New ReviewPi day is both delicious and informative! Play a short video on Pi Day to explain the basics behind both the holiday and the infinite number.

New ReviewBefore you can do anything with circles, you need to know the parts of the circle. Viewers of a short video see how to label relevant information about a circle. The resource covers radius, diameter, circumference, chord, tangent, arc,...

Calculating circumference is as easy as pi times diameter. A short video explains how to measure pie tins using the diameter. It also describes the relationship between diameter and circumference. Using the knowledge, scholars consider...

Work backwards if you dare. Scholars view a video to learn how to apply the area formula of a circle to solve problems. They watch an example where the focus is finding the radius of a circle given its area, requiring the use of inverse...

How can you make a circle with x's and y's? A video tutorial explains how to write the equation of a circle with a center at the origin. The tutorial also demonstrates how to analyze the equation. Following the lesson, pupils use the...

There's no way around it—learners must use trigonometry to model the line of sight around a race track! Using the starting line as the origin, pupils model the straight line distance to any car using a trigonometric expression. The...

Circles are ripe with theorems. Viewers of a YouTube video watch as the narrator describes a set of eight theorems on circles. The video shows a diagram for each theorem and provides a brief explanation for each one.

Just how durable could a hollow ball bearing be? Learners model the strength of the walls of a ball bearing as a function of the radius of its cavity. They use their models to make reasonable conclusions about the probability of failure...

A tangent line always finds its place at a 90-degree angle to a radius. Many scholars struggle with the proof of the seemingly simple statement. A brief video demonstrates the reasoning behind the proof before pupils practice applying it...

Model a bicycle chain with circles and tangent lines. Given the dimensions of the sprocket wheels, young scholars calculate the length of the chain that surrounds them. A second task has learners write a function for the length of a...

Round and round and round we go. Given a diagram of three circles, two of which share a point with the third circle, learners identify the radius of each circle. Doing so requires setting up and solving a system of equations based on the...

Gotta catch them all—no learner left behind! Young scholars must predict the length of time it takes a phone attached to a fan to travel five kilometers given the radius and rotations versus time data. Why would you attach a phone to a...

Double the pizza? What a great deal! Young pizza enthusiasts investigate two different coupons, one that doubles the radius and one that doubles the sector angle of a slice. They determine which coupon is the better deal.

As the saying goes, a penny saved is a penny earned. Young scholars use a penny activity to earn their way to an understanding of volume. Given three different-sized cylindrical containers, individuals make calculations to determine the...

Yes, knowing math can make you better at sports. Small groups solve a problem involving soccer players passing a ball to score a goal. Successful solutions to the problem require using knowledge of lines and angles.

Roll out the red carpet for an exemplary lesson. Using the dimensions of a rolled piece of carpet, learners calculate the dimensions of the flat sample. Pictures provide individuals with the information they need to make a valid conclusion.

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...

Round and round you'll go! Learners watch as different-sized circles fill with coins. They collect data and then make a prediction about the number of coins that will fit in a large circular rug.

Explore Apple's spaceship office building. Built in the shape of a circle, the office building offers a unique floor plan challenge. Young scholars use the dimensions of the building to estimate the square footage for each employee. 

Your classroom will overflow with learning as they analyze the volume in a pot of meatballs. Young mathematicians predict the number of meatballs that will make a pot of sauce overflow. They incorporate both the volume of cylinders and...

It really is as easy as pi. The segment of a massive geometry playlist points out that the formula for the area of a circle is a relatively simple one. Using the formula, the presenter shows examples of finding the area of circles.