Curated OER
Super Shapes Part 2 - Circles
Through the use of Internet, video, and hands-on activities, youngsters learn the parts and characteristics of a circle. This fantastic lesson plan has some excellent website activities included in the plan. Your kids will have a much...
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...
Curated OER
Inscribing a Square in a Circle
Inscribing a square in a circle brings up a number of interesting geometry topics including triangle congruence and how to prove a quadrilateral is a square. This activity is followed up by finding the area of the square and determining...
Curated OER
Area of Circles and Probability
Students investigate the area of squares and circles. For this geometry lesson, students calculate the area and probability of simple events. They work on a laptop using Safari.
PBS
Scale City — Scaling up Recipes and Circles in the Real World
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....
MENSA Education & Research Foundation
Pi Day Fun!
In this multi-faceted introduction to pi, participants perform a bevy of pi-related activities. Ranging from measuring household items to singing pi songs and reading pi stories, this fun and non-intimidating resource serves to bring up...
Illustrative Mathematics
Slopes and Circles
An upper-level treatment of what is often presented as a basic concept (the right angle of an inscribed circle on the diameter), this activity really elevates the mathematical thought of the learner! Expected to develop formulas from...
Virginia Department of Education
Angles, Arcs, and Segments in Circles
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...
Dick Blick Art Materials
Start with a Circle...
The Golden Ratio. The Divine Proportion. Yup. It's math and art blended into one colorful activity. Young artists combine colored tissue paper circles and parts of circles to create geometric patterns. As a bonus, kids get to figure out...
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...
Mascil Project
Circular Pave-Stones Backyard
Pack the lesson into your plans. Young mathematicians learn about packing and optimization with the context of circular paving stones. They use coins to model the paving stones, and then apply knowledge of circles and polygons to...
Curated OER
Discovering Pi/Welcome to Pi Day
Students explore pi. In this circle measurement lesson, students define and identify radius, diameter, circumference, and perimeter. Students work in groups to measure several plastic lids and record their findings. Students compare the...
Curated OER
Pi Day: The Other Math Holiday!
Happy Pi Day! This collection of games, experiments, and activities leads participants through an exploration of the many aspects and attributes of that mysterious quantity, pi. Activities range from using statistical experimentation to...
EduGAINs
Discovery of Pi
Serve up a slice of math for Pi Day! A combination of fun, hands-on lessons and helpful worksheets encourage learners to practice finding the radius, diameter, and circumference of different circles.
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...
Radford University
Discover Radians!
No need for radians to be mysterious. Scholars use a cardboard cut-out of a unit circle and measure the radius and circumference using a piece of string. They consider the number of radii needed to cover the entire circumference and use...
Curated OER
Around the Clock
Middle schoolers discover the relationship between the circumference of a circle and its diameter. They find the length of an arc of a circle.Students use estimation strategies in real-world applications to predict results (i.e.,...
Curated OER
Chords of a Circle
Teach how to differentiate between chords and perpendicular bisectors. In this geometry lesson, young scholars relate the properties of chords and circle to solving right triangle. They define what makes two chords congruent in side a...
Curated OER
Match The Graph Circles
High Schoolers engage in a study of circles and graphs that are related with the focus upon finding the center and radius. The lesson includes the suggestion of giving homework using circle problems before this one to create background...
Early Childhood Education
Shape It Up!
The best way to understand shapes is to make them. Young geometers explore basic shapes through a variety of gross motor and fine motor activities. Shape sorting, singing songs about shapes, and eating shape snacks are just a few of the...
EngageNY
Tangent Segments
What's so special about tangents? Learners first explore how if a circle is tangent to both rays of an angle, then its center is on the angle bisector. They then complete a set of exercises designed to explore further properties and...
5280 Math
Pythagorean Triples
From Pythagorean triples to the unit circle. Learners use the Pythagorean Theorem to find Pythagorean triples and then relate their work to the unit circle in a fun algebra project. Their discovery that x^2+y^2 is always equal to one on...
Pie Council
National π Day
Learners can enjoy pi with pie! A collection of short activities celebrates pi day with a word search, a maze, and real-world problemsn. Using pi in formulas for area, circumference, and volume as well as exploring simple fractions is...
101 Questions
Brita
It's hard to envision what 39 billion plastic bottles look like. Brita claims that the US uses that number of plastic bottles each year! If that's not enough to get your attention, figure out how many times 39 billion water bottles can...