EngageNY
The Most Famous Ratio of All
Pupils develop a definition of a circle based upon its radius in the 17th segment of a 28-part series. They determine the relationship between the radius and the diameter of a circle. To round out the lesson, they use the formula for the...
Curated OER
Measuring the Area of a Circle
When mathematical errors happen, part of the learning is to figure out how it affects the rest of your calculations. The activity has your mathematicians solving for the area of a circular pipe and taking into consideration any errors...
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...
Illustrative Mathematics
Seven Circles III
A basic set-up leads to a surprisingly complex analysis in this variation on the question of surrounding a central circle with a ring of touching circles. Useful for putting trigonometric functions in a physical context, as well as...
Mrs. Burke's Math Page
The Amazing Pi Race
Add a sense of excitement to your math class with this race across the country. Using their knowledge of all things circular, young mathematicians work in pairs answering a series of pi-related word problems as they hop from one city to...
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...
101 Questions
Car Caravan
Keep playing with those old toy cars! Pupils estimate the number of toy cars in an art installation. The only information they receive is a picture showing the toy cars arranged in concentric rings and the diameter of the overall...
Curated OER
Worksheet for Pi
Who needs a pie-eating contest when you have a pi-ology game! Celebrate March 14th with a fun board game about pi and other geometric concepts. As learners answer questions about geometry, they move around the board to collect...
TOPS Learning Systems
PI in the SKY
What is pi anyway? After this set of activities, your pupils should have multiple answers to this question. Investigate pi with various experiments and discoveries. Calculate the ratio circumference/diameter for different sized...
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...
101 Questions
Wedding Cake Ribbon
Customers often want ribbon around fancy cakes, but how does a baker know how much ribbon to buy? Scholars view a cake with multiple layers in different geometric shapes. They must figure the perimeter and circumference and add them...
Virginia Department of Education
Arc Length and Area of a Sector
What do skateboarding and baked goods have in common with math? You can use them to connect half-pipe ramps and cakes to arcs and sectors. Pupils compare the lengths of three different ramp options of a skate park. They calculate the...