You should introduce the basic concepts behind the melting and freezing points of ice and how ice reacts with different substances, for example. Introduce the experiments that you are planning to carry out with your young scientists, including covering any health and safety elements of the hands-on science. Ask your children to then write down a hypothesis of one or two sentences explaining a prediction for each of the experiments that you will carry out.
Have your youngsters start with a simple project investigating how different amounts of salt will melt ice. Instruct young scientists to fill an ice cube tray with distilled water so each individual compartment contains the same amount of water. Have youngsters line up four glass beakers next to one another before dropping an ice cube in each one; label one beaker as "control" and do not add any salt. Elementary students should then add one, two and three teaspoons of salt to the beakers with the other three ice cubes, making sure to mark the beakers with the relevant amount of salt by writing "one," "two" and "three." Your youngsters should ask a classmate to start a separate timer for each beaker once the salt is added. Young scientists should stop the timer once the ice cube has melted completely, known as the melting point, before comparing salt levels and the melting rate of ice.
Elementary students can carry out an investigation to look at how several different substances, such as cola, soda water, salt water, sugar water and black pepper, melt ice. Prepare an ice tray with same-sized ice cubes. Students should prepare any solutions that will be used during the experiment, such as a medicine dropper of water with two teaspoons of salt or sugar added. Get your young scientists to line up identical ice cubes in identical shallow dishes and place a stopwatch next to each dish. As the substance is added to the ice cube, such as a medicine dropper of cola, your experimenting elementary student should start the stopwatch and stop it once the ice has melted completely. Students should compare the length of time it took ice to melt when exposed to different substances.
Educate your youngsters about the safe way to handle hot water before assisting your students with this experiment. Students should take two identical polystyrene cups and fill one two-thirds of the way with cold water and the other with hot water from the faucet. Make sure youngsters label each cup to show whether it is hot or cold water before placing each one in a freezer and starting a timer. Instruct elementary students to check back on the two cups once every 20 minutes and note the changes in each cup — young scientists will note that the hot water starts to freeze before the cold water, which is known as the "Mpemba effect."