Unit Plan
Texas Education Agency

Texas Gateway: Determining Area of Composite Figures

For Students 7th - 8th
Given composite figures (combinations of rectangles, squares, parallelograms, trapezoids, triangles, semicircles, and quarter circles), students will be able to determine expressions for the area as well as calculate the area of the figure.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: 8.g Circle Sandwich

For Teachers 8th Standards
Eighth graders are presented with a drawing of a large square inscribed by a circle which is itself inscribed by a second square. They are asked to find the area of the circle outside the smaller square and compare it to the area of the...
Interactive
Calculator Soup

Calculator Soup: Surface Area Calculator

For Students 9th - 10th
Online calculator to calculate the surface area of geometric solids including a capsule, cone, frustum, cube, cylinder, hemisphere, pyramid, rectangular prism, sphere, spherical cap, and triangular prism
Interactive
PBS

Pbs Learning Media: Square Wheeled Tricycle: Radius and Circumference

For Students 6th - 8th
This interactive exercise focuses on working with the radius of various circles to find the circumference and area as well as challenging you to find the distance a square wheel travels around the track.