Children will need to go outside during this experiment. Challenge children to find as many different hibernating insects as possible and, without disturbing the insects or spiders too much, observe them using magnifying glasses. If possible, locate a gall (a piece of bile from an animal) and carefully cut it in half to see what's inside. To help boost children's long-term understanding, cut a six-inch length of twig that has a gall attached and put it in a glass jar with three cups of soil. Moisten the dirt occasionally. Keep the galls outdoors, out of direct sunlight. Have children observe it once a week. When spring arrives, children can see which insects emerge from hibernation.
To start this project, ask children to think about how society deals with the problem of icy sidewalks and roads through the use of industrial salt. Then complete a project using four ice cubes. First, have children weigh each ice cube in grams and note the weight of each. Students should then place each cube on a saucer and subject each one to a different substance, such as table salt, sea salt, pure vinegar and a store-bought ice-melting product. Start a timer. After 10 minutes, pour away excess water and weigh the ice cubes again. Children should note the difference between start and end weights before determining which substance is most effective for melting ice.
For this experiment, you'll need two one-liter glass jars and a box large enough to fully contain one of the jars with at least two inches of space around the entire outside of the jar. Have children place one jar in the box and surround it with as many cotton wool balls as possible. Place the other jar next to the box, and add two cups of warm tap water to each jar. Add a thermometer to each jar for one minute to record the starting temperature. Remove the thermometers and seal both lids. Wait 20 minutes and record the new temperature in each jar. Discuss with children how the box with cotton wool balls, which replicates animals' hair, keeps the water in the jar warmer.
Have children mix one and a half cups of water and 500 grams of cornstarch in a bowl and stir until there is hardly any standing water left. Lay a sheet of wax paper flat on a table and place a tablespoon of the mixture in the center of the paper. Have children observe its characteristics, which replicate the movement of glaciers. Then have children add another tablespoon of the cornstarch mixture on top of the existing amount and note how the two interact. Then have them mix together sand, fine gravel and soil, and sprinkle a cup of this mixture around the perimeter of the glacier before adding a sprinkling of soil on top of the glacier, which replicates rocks and soil from the earth's surface in the glacier. Have children continue to add more of the cornstarch mixture on top of the center of their glacier, paying particular attention to the reaction when it arrives at the perimeter of soil, sand and gravel.