Two metal cubes and a metal slab, all painted the same color, allow students to discover the relationships of mass, volume, and density. The cubes have the same volume but differ in mass and density. 1 cube is steel, 1 cube is aluminum, and the slab is aluminum. Also includes 2 - 15cm scales (rulers) and an instruction sheet. Great for home school, science fairs, classroom demonstrations and STEM activities. The Science Source, 16243.