Imagine a pot of soup bubbling on the hob. Why is the handle plastic or wood, not bare metal? Hands up: which spoon do you think will stay cooler longest in warm water, metal, wood or plastic?

A heat conductor lets heat travel through it quickly, like a metal pan on the hob.

A heat insulator lets heat travel through only slowly, like a wooden pot handle or an oven glove.

Look around the room: point to something that should be a conductor, then something that should be an insulator. Why might a pan be metal but its handle wood?

Our class question: which spoon handle warms fastest in warm water, metal, wood or plastic? In your group, say your prediction and one reason. Predictions are the start of the science, not a test to get right.

Your group plans a fair test. Every group follows this plan:

1. Change: only the spoon material (metal, wood or plastic).
2. Measure: time until the handle feels warm (same judge, same fingertip, stopwatch).
3. Keep the same: cups, water amount, water warmth, spoon depth, and who judges.
4. Three trials for each material so we can choose a middle reading later.

Before any water is poured, write your plan at the top of your Investigation Journal page: change, measure, keep the same. Then draw your test in the box under the plan: one cup, the water and a spoon. Label the handle and the place the judge's finger goes.