Lesson Plan
Illustrative Mathematics

Lines of Symmetry for Quadrilaterals

For Teachers 3rd - 5th Standards
Explore how lines of symmetry help define different categories of quadrilaterals. Looking at a square, rectangle, trapezoid, and parallelogram, young mathematicians discover that each shape has its own, unique symmetry. Encourage your...
Activity
101 Questions

Viewmongous TV

For Teachers 6th - 8th Standards
Just how big of a TV do you need?! The task at hand asks individuals to compare the area of 80-inch and 55-inch TVs. The length of the TV is given and learners must use the Pythagorean Theorem to determine the width to calculate the areas.
Lesson Plan
Illustrative Mathematics

Area of a Trapezoid

For Teachers 7th - 9th Standards
Here is a straightforward example of how to apply the Pythagorean Theorem to find an unknown side-length of a trapezoid. Commentary gives additional information on proving that the inside of the trapezoid is a rectangle, but is...
Activity
PBS

Paper Table

For Teachers 4th - 8th
What is black and white and re(a)d all over? Class members build a table out of rolled newspapers. Pupils follow the design process to design, build, and test their paper tables in the second challenge in a series of five.
Activity
101 Questions

Retina Display

For Students 6th - 8th Standards
Learners calculate the pixel density of a specific cell phone using the concept of similarity. They use information from the cell phone's website to make their calculations and then compare their results to the posted information.
Activity
101 Questions

Snail's Pace

For Teachers 6th - 8th Standards
Time doesn't fly when you're watching a snail cross a sidewalk. Combining the concepts of the Pythagorean Theorem and the distance, rate, and time formula, learners determine how long it takes a snail to go from one corner of a sidewalk...
Activity
Curated OER

Geometric Pictures of One Half

For Teachers 3rd Standards
A learning task that involves creative ways of thinking permits children to use paper models as a way to visualize the fraction one-half. Learners can fold or cut their models in such a way that the unshaded regions, and shaded...
Activity
Annenberg Foundation

Annenberg Learner: From Corner to Corner

For Students 2nd - 5th Standards
Measure the lengths and diagonals of three squares with a ruler. Look over your measurements and try to come up with a rule of thumb for estimating the length of a diagonal if you know the length of a side.
Activity
Discovery Education

Discovery Education: Web Math: Find Out Things About a Square

For Students 9th - 10th
WebMath will calculate the side length, diagonal length, perimeter, area, or volume, given the side, perimeter, diagonal, or area. This site also displays formulas for a square.