We use basic units of measurement to break down things and communicate clearly. The first lesson in an 11-part series teaches the proper way to measure various items. It starts simply with measuring the dimensions and areas of geometric...

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. 

What do we do when a dive is too dangerous for humans to accomplish? Send in the robots! Middle school scientists get acquainted with several different models of submersible robots in the second lesson of six from NOAA. Lab groups then...

Certain things just do not mix, including liquids of varying densities. Learners collect data to determine the densities of several liquids. They then use the density information to predict the type of liquid.

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...