Make holes in the jar lids large enough for a
thermometer, but seal with a blob of modelling clay.
2. Wrap foil around one of the jars, bubble wrap around
another and a woollen scarf around another. Leave one
jar bare.
3. Heat water (under adult supervision) and pour carefully
into four jars. Screw the tops on each.
4. Measure each with the thermometer straight away and
record the temperature.
5. Repeat the test every two minutes by leaving the
thermometer in each jar for a few seconds to get
a true reading. Record each on the graph.
6. What do you find?