Distribute sheets to students.
For young primaries use instead of a thermometer to measure how warm or cold water is, or to show how we can measure temperature. (Then show them a thermometer.)
For outdoor activity, all grades, using the sun's radiation:
Allow them to discover that the sun changes the colour of the sheets.
Give them the colour scale (for my sheets, coolest is black, then getting warmer is red, orange, yellow, blue, then black again, so black can either be coolest or warmest).
Allow students to explore the environment with their sheet.
If they need suggestions, see the photos:
block the sun's radiation with your hand/playground structure to make an image on the sheet
use the sheet to measure how warm different playground structures are
use the sheet to measure relative heat given off by differently-coloured walls
use a heat pad to change the colour of the sheet
use tubs of cool or warm water to cool and warm the sheet respectively
use drips of water to make patterns and paint on the sheet
For an indoor activity, older primaries and up, use infra red heat lamps.
Students 'charge' their sheets at the heat lamp (by radiation). Then quickly press the sheets to surfaces and objects in the classroom, where they will lose their heat by conduction.
Or students can heat up the sheets with their hands, speeding it up with friction (rubbing sheet against hands or carpet).
Discuss what kinds of heat transfer heated the sheets up:
Radiation from the sun.
Conduction when the sheet is pressed against a surface or water draws heat from the sheet.
Use the sheets to determine whether something is a conductor or insulator (best done as a class in a circle at a carpet);
All together, press hand on the sheet for 5 seconds, then see the colour change as it heats up.
Then, once the sheets have cooled again, lay tin foil over the sheet and press hands for 5 seconds again - the same heated pattern emerges. Tin foil is a 'conductor' of heat.
Then, once the sheets have cooled again, lay felt over the sheet and press hand for 5 seconds again - no colour as the felt blocks heat from transferring from the hand to the sheet. The felt is an 'insulator'.
Water cools the sheet really fast, and makes awesome patterns if water is dripped or painted on the warm sheet.
Use heat sensitive sheets to show how a tool like this helps us detect subtle changes in heat (show Infra red images) whereas some animals have their own sense organs which can detect these changes e.g. snakes.
