American Heart Association
Pi Day
Did you know a mathematician's favorite dessert is a fruit "pi"? By participating in a fruit cutting activity, young mathematicians realize one constant—the ratio of a circle's circumference to its diameter is always pi. It is a perfect...
Curated OER
Perimeter: The Distance around a Shape
A few good questions move this lesson right along. Young mathematicians use critical-thinking skills as they learn how to determine the perimeter of various shapes. They determine perimeter first by measuring and adding the lengths of...
Mrs. Burke's Math Page
Let Them Eat Pi
Looking for a fun and creative way to celebrate Pi Day? Then this is the resource for you. From a scavenger hunt and trivia contest to PowerPoint presentations and skills practice worksheets, this collection of materials is a...
Illustrative Mathematics
Running Around a Track II
On your mark, get set, GO! The class sprints toward the conclusions in a race analysis activity. The staggered start of the 400-m foot race is taken apart in detail, and then learners step back and develop some overall race strategy...
Curated OER
Exploring Diameter and Circumference
Learn how to identify the diameter and circumference of a circle. Then, collect data on a circle and relate it to the diameter and circumference of a circle. Last, plot data and find the line of best fit.
Curated OER
An Introduction to Pi and the Area of a Circle
Young scholars explore measurements of a circle. In this lesson about circumference and radius, students practice calculating measurements of a circle. Young scholars estimate, calculate, and practice with graphing all while learning...
Curated OER
The Circle's Measure
Listen to the story "Sir Cumference and the Dragon of Pi" and solve the riddle and to save Sir Cumference from the knights. Your students will love mixing an activity with story and will practice their measuring skills while...
National Wildlife Federation
What is DBH?
When measuring the circumference of a tree, does it matter how high you place the measuring tape? Most scholars have never considered this question, but scientists know that measurement techniques must be standardized. The 13th lesson in...
Virginia Department of Education
Going the Distance
Estimate the value of one of the most famous irrational numbers. The hands-on instructional activity instructs classmates to measure the circumference and diameters of circles using yarn. The ratio of these quantities defines pi.
Flipped Math
Circles and Arc Lengths
Discuss all things round and round. Pupils review finding area and the circumference of circles and use them to solve problems. Next, they learn about central angles and their relationships to measures of arcs. Learners then find out how...
EngageNY
The Inscribed Angle Alternate – A Tangent Angle
You know the Inscribed Angle Theorem and you know about tangent lines; now let's consider them together! Learners first explore angle measures when one of the rays of the angle is a tangent to a circle. They then apply their...
Curated OER
Perimeter of a Circle Worksheet
In this perimeter of circles learning exercise, students find the perimeter of 6 circles given a diameter. Students find the perimeter in terms of Pi.
Curated OER
All About Circles Post Test
In this geometry instructional activity, students answer ten multiple choice facts about circles. The questions include finding the diameter, area, and radius of a circle.
Curated OER
Leveled Problem Solving Circumference of a Circle
In this geometry instructional activity, 6th graders solve 6 word problems in which they find the circumference of items that are circles. They find the circumference of items such as a basketball hoop, a cereal bowl, and a circular frame.
Curated OER
Parachutes, Circles and Pi...Oh My!
Students explore different size circles to discover the relationship between diameter and circumference. In this circles and Pi lesson, students construct simple parachutes using circle patterns of varying sizes. Students predict the...
Curated OER
Circle Circus
Third graders find the radius and diameter of a bubble. In this radius and diameter lesson, 3rd graders create bubbles on their desk and find the radius and diameter of the bubble. Students work in partners to define circle terms and...
Illustrative Mathematics
Right Triangles Inscribed in Circles II
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...
Willow Tree
Area of Common Geometric Figures
Scholars can use area formulas, but can they apply what they know about area? The lesson challenges learners to think logically while practicing finding area of shapes such as rectangles, circles, parallelograms, triangles, and other...
National Gallery of Canada
Counting Circles
Learners look at bands of colors and estimate how many rings of color there are. While working in groups, they come up with a plan of how to accurately count the rings. They attempt to find a pattern in the colors, and decide whether...
Curated OER
Calculate the Diameter
In this diameter worksheet, 6th graders find the diameter of 5 circles. Students are given the formula for circumference and circumference information along with a blank box to complete their work.
Curated OER
Circles-Diameter, Circumference, Radius and the Discovery of Pi
Seventh graders measure the diameter, circumference and radius of a circle and find pi using the diameter and circumference. In this geometry lesson plan, 7th graders work in groups to find the diameter, radius, and circumference of...
Curated OER
Task: Grain Storage
Farming is full of mathematics, and it provides numerous real-world examples for young mathematicians to study. Here, we look at a cylinder-shaped storage silo that has one flat side. Given certain dimensions, students need to determine...
101 Questions
Rotonda West, FL
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...
Penn Museum
Penn Museum: China Gallery
Invite your learners to take a closer look at the art and mathematical function of dome buildings as designed by the ancient Romans. In the next segment of this attractive worksheet set, your young historians will then learn about...