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Curated OER
Solid Rocket Boosters-II
In this solid rocket boosters worksheet, students solve 2 problems using a grid showing a cross section of a proposed solid rocket booster. Students complete the grid and shade the rings of combustion in 15-second step intervals. They...
Illustrative Mathematics
How Many Leaves on a Tree? (Version 2)
A second attack at figuring out the number of leaves on a tree, this activity makes both an excellent follow-up to version 1 and a stand-alone activity. Learners practice setting parameters and deciding acceptable estimate precision, and...
Mathematics Vision Project
Module 5: Modeling with Geometry
Solids come in many shapes and sizes. Using geometry, scholars create two-dimensional cross-sections of various three-dimensional objects. They develop the lesson further by finding the volume of solids. The module then shifts...
Curated OER
Probability and Geometry Problems
In this online math learning exercise, high schoolers consider a variety of scenarios which include elements of geometry and probability. This excellent resource allows the students to check their answers, and to get "hints" should they...
Curated OER
Non-Unit Fractions
First graders explore non-unit fractions. They discuss the parts of fractions and identify the numerator and the denominator. They discuss various examples of fractions. Students write fractions that are equivalent to the ones written by...
Khan Academy
Khan Academy: Shaded Areas
Find the areas of shaded regions which are combinations of squares, triangles, and circles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Science Buddies
Science Buddies: Thinking in (Semi )Circles: The Area of the Arbelos
The arbelos is the white-shaded region between the three semicircles in the illustration at right. In this project, you'll prove an interesting method for determining the area of the arbelos.
CK-12 Foundation
Ck 12: Area of Sectors and Segments: Pacman Area
[Free Registration/Login Required] Students are to determine the area of the shaded region between two radii. Click challenge me to answer practice questions and click learn more to watch a video.