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 ReviewIf angles intercept the same arc, the angles must be the same size. The quick video talks through the proof of showing the reason two inscribed angles that intersect the same arc have the same measurement. Pupils then create their own...

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,...

New ReviewCircumference and diameter differ by just a factor of pi. A short video shows viewers how to calculate circumference given the diameter. It also gives an example of determining the diameter given the circumference.

New ReviewCommunication is the key. A presentation provides 25 sample items for Claim 3, Communicating Reasoning, for the Smarter Balanced High School Math assessment. Items require pupils to answer the question and provide logical reasoning to...

New ReviewProblem solve across the content standards. The presentation slides provide 19 sample items from the Smarter Balanced high school assessment. Items illustrate Claim 2, problem solving, of the test and are drawn from all the high school...

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...

What a great big skillet you have. The resource introduces the class to the world's largest stainless steel skillet. The class creates a model of the skillet and a typical 12-inch skillet and compares the relative sizes of their areas....

Here's some very interesting circles for your very interested pupils. A performance task requires scholars to sketch a pair of orthogonal circles so the centers are the endpoints of one side of a triangle. They draw an additional circle...

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...

No math lesson would be complete without examples. A short video works through examples highlighting circle theorems. This includes problems where individuals must take multiple theorems into account to determine the solution.

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.

A geometry module connects algebraic reasoning to geometry. It challenges scholars to investigate the slope criteria for parallel and perpendicular lines, prove theorems involving coordinate geometry, and write equations for circles and...

Circles, circles, everywhere! Pupils learn all about circles, central angles, inscribed angles, circle theorems, arc length, area of sectors, and radian measure using a set of 12 lessons. They then discover volume formulas through...

And round and round the park we go! Given a description of an amusement park with the locations of three attractions connected by walkways, learners consider what happens when additional attractions join the mix by doubling the length of...

Come full circle in learning about conic sections. Learners first look at the type of conic section formed when concentric circles intersect a standard coordinate plane. They then see which type forms when two sets of concentric circles...

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...

What do you call a quadrilateral in danger? A peril-lelogram! Scholars avoid danger by proving the opposite angles in a quadrilateral add up to 180 degrees. After viewing a brief video, they complete textbook exercises and a practice...

Scholars ponder the proof relating the center angle and circumference using a demonstrative video. Additional worksheets and textbook practice helps them demonstrate their intellect.

Trigonometry teachers often go off on a tangent, and here's a learning exercise that proves it! First, young mathematicians use a formula with tangent to prove a formula correct for area. Then, they draw conclusions about the area of a...

There's no need to go to great lengths to learn about circles. Young mathematicians view a short YouTube video on how to find arc lengths of circles. The video covers a few examples highlighting the method of determining arc length in...

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...

Don't run from the resource—sprint to it. Using an engaging performance task, scholars consider a set of constraints on the creation of a track. Given several possible designs, they determine if the designs meet the constraints. If not,...