Properties of materials: sticky, stretchy, foaming, floating

Choose a selection of these activities, to explore properties of materials.

Watch the motion of molecules, by looking at fat droplets in milk being bumped by water molecules. This can be a small group activity, or set up on the side of a classroom for students to visit in their own time.

Watch how molecules move faster and slower in cold and warm water respectively. Best as a demonstration at the start or end of the lesson.

A selection of the following activities can be stations that the students rotate through. Ordered by what I consider most effective.

Make glues from household materials, to explore sticky properties of materials. Discuss with older students their molecular nature - that some glues work because long molecules reach into the tiny cracks in the materials to hold them together.

Test the stretchiness of elastic bands, and how combinations of bands change this stretchiness.

Experiment with density and buoyancy with Directed challenge 2, then discuss why things float and sink in terms of how closely packed the molecules are in solids, liquids and gases.

Build molecule models, to see how molecules are different shapes, are made up of different atoms, and have different functions.

Test materials for how well they conduct electricity. This is a property of materials that have free electrons, that can make a current.

Test materials for how well they make foam in water, then discuss the molecular nature of foaming molecules. Foam-making molecules have a water-loving part and a water-hating part, so that they surround air bubbles and stabilize them to form foam.

Classify common materials by how rigid, elastic and malleable they are, and discuss differences at the molecular level.