Shodor Education Foundation
Triangle Area
While the lesson plan focuses on right triangles, this activity offers a great way to practice the area of all triangles through an interactive webpage. The activity begins with the class taking a square paper and cutting in in half; can...
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...
Teach Engineering
Determining Densities
Don't be dense—use a robust resource. The second installment of a five-part Floaters and Sinkers unit has learners determine the densities of several objects. As part of the activity, they learn the displacement method for finding...
Teach Engineering
Density Column Lab - Part 1
Mass and density — aren't they the same thing? This activity has groups use balance beams and water displacement to measure several objects. The pupils use the measurements to calculate the density of the objects.
Teach Engineering
Density Column Lab - Part 2
Groups suspend objects within layers of liquids to determine the densities of different liquids and compare them to the densities of objects calculated in Part 1. The groups then carefully test their calculations by layering the liquids...
Teach Engineering
Surface Tension Lab
What constitutes a good soap bubble? In the second installment of a nine-part series, scholars apply their understanding of surface tension to soap bubbles. They experiment to determine the best solutions to use for the...