Refine Your Results

Content Curators



Resource Types


Now... gain access to over 2 Million curated educational videos and 500,000 educator reviews to free & open educational resources

Get a 10 Day Free Trial

364 resources with the concept diameter

Videos (Over 2 Million Educational Videos Available)
How Computers Work: What Makes a Computer, a Computer? Video
How Computers Work: What Makes a Computer,...
Defining Gravity Video
Defining Gravity
Thomas Jefferson - Author of The Declaration of Indepence & 3rd U.S. President | Mini Bio | BIO Video
Thomas Jefferson - Author of The...
Other Resource Types (364)
Lesson Planet

The Outer Planets: Grades 6-8

For Teachers 6th - 8th Standards
A long time ago, a galaxy formed that contained a solar system with eight planets—or nine depending on who is counting. A collection of 22 lessons has middle schoolers examine the Outer Planets of the solar system. They calculate the...
Lesson Planet

High School Balanced Packet 2 Assessment Tasks

For Students 9th - 12th Standards
Good assessments can be hard to find and difficult to formulate. Designed as a collection of mathematics assessment tasks, the 20 resources in this packet can also be used as lesson openers, a review, or extra practice. The open-ended...
12 Items in Collection
Lesson Planet

Math Antics Geometry Video Lessons

For Teachers 4th - 8th Standards
The point of this collection of 12 videos is to introduce learners to three basic parts of geometry—points, lines, and planes. The presenter provides definitions, shows how to classify shapes, provides examples, and shows how to use...
Lesson Planet

Fibers, Dyes, and the Environment

For Students 6th - 12th Standards
Nanofibers can be made through electrospinning or force spinning in order to reduce the negative impact on the environment. Pupils study the role of fibers and dye on the environment through a series of five hands-on activities. Then,...
Lesson Planet

What is DBH?

For Teachers 9th - 12th Standards
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 Planet


For Students 9th - 12th Standards
Don't circle around the topic, but get right to the center with tons of practice regarding circles in geometry. The note-incorporated learning exercise provides guided practice through many topics such as central angles, inscribed...
Lesson Planet

Eighteen Flavors

For Teachers 7th - 8th Standards
Your learners will be tantalized by this inquiry-based, collaborative activity as they discover how to write an equation that represents the height of an ice cream cone. Given the scenario based on the poem, "Eighteen Flavors," and...
Lesson Planet

Circles: Radius, Diameter and Circumference

For Students 4th - 11th
Fascinating discussion regarding the origin of Pi accompanies a detailed explanation of how to find the circumference of a circle. Since this is the first installment in a series on circles, the concept of circumference is separated into...
Lesson Planet

Area of a Circle

For Students 7th - 10th
A second installment in a series on circles, this production demonstrates the process of finding the area of a circle. As an introductory tool, it is effective. However, it does not explain the reasoning behind the formula because that...
Lesson Planet

SAT Prep: Test 1 Section 3 Part 4

For Students 9th - 12th
Pushing through to problems 11-12 on page 398 of The Official SAT Study Guide, Sal goes into comprehensive detail on each problem. Problem 11 involves geometry, including the function of pi, and problem 12 involves non-constant slopes....
Lesson Planet

SAT Prep: Test 3 Section 2 Part 3

For Students 9th - 12th
Math speeds along in this video, which takes students through problems 11-15 on the practice SAT. Sal takes care to show students more than one possible way to solve several problems, allowing them to make the choice based on their own...
Lesson Planet

SAT Prep: Test 4 Section 4 Part 1

For Students 9th - 12th
The next section of the practice SAT from The Official SAT Study Guide (page 594) covers simple linear equations and geometric figures. Students will appreciate Sal's quick problem solving and thought process, which is easy to understand...
Lesson Planet

SAT Prep: Test 3 Section 8 Part 2

For Students 9th - 12th
Problems 7-9 involve exponents, inequalities, and geometric figures (diameter and radius), all of which Sal explores eagerly. After misreading one problem, he takes care to correct his mistake, showing students how important it is to...
Lesson Planet

Test 2 Section 2 Part 5

For Students 9th - 12th
Both algebra and geometry problems are featured in this SAT practice video. Students who have a hard time transitioning between skills on tests (average mean, then diameters and pi, then positive integers) would benefit from Sal's deft...
Lesson Planet

Circumference and Areas of Circles

For Teachers 7th - 12th Standards
Middle and high schoolers listen to a scenario about a puppy and use the scenario to develop formulas in order to find the area of a circle. In this circumference lesson, pupils understand how to find the radius, diameter, area of a...
Lesson Planet

Discovering Pi/Welcome to Pi Day

For Teachers 9th - 12th
Learners explore pi. In this circle measurement lesson, students define and identify radius, diameter, circumference, and perimeter. Learners work in groups to measure several plastic lids and record their findings. Students compare the...
Lesson Planet

Super Shapes Part 2 - Circles

For Teachers 5th - 6th
Through the use of Internet, video, and hands-on activities, youngsters learn the parts and characteristics of a circle. This fantastic lesson has some excellent website activities included in the plan. Your kids will have a much greater...
Lesson Planet

Circles in Geometry

For Teachers 3rd - 6th
Students figure the diameter and circumference of a circle. In this circles lesson, students break into small groups and work together to find the answers then compare with peer groups. Students then make human circles and using string...
Lesson Planet

The Circle's Measure

For Teachers 6th
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 completing...
Lesson Planet

Sports Bag

For Teachers 6th - 8th Standards
Lay it out using the least amount of material. Learners use the dimensions of a cylindrical sports bag to find out the size of pieces of material needed to sew them. The pupils find the best placement of the pieces to use the least...
Lesson Planet

Measure the Diameter of the Sun

For Teachers 6th - 12th
Measuring the diameter of the sun may get a little heated, but using an indirect approach can help individuals keep their cool. Learners use the reflection of the sun to measure how long it takes for it to move one diameter. Using the...
Lesson Planet

Pi Day #1a – Discovering Pi

For Students 6th - 10th Standards
Unravel 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...
Lesson Planet

Pi Day | All About the Holidays

For Students K - 4th
Pi 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.
Lesson Planet

Formulas for Circle Area and Circumference: Simple as Pie

For Teachers 6th - 7th Standards
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...