Perfect! An art/science fusion project on www.placeofourown.net.
Fill a disposable paper cup, cardboard milk carton, or other container with water and freeze over night. Let your child help you remove the ice from the container and place it on a cookie sheet to catch the melting ice water. Let your child sprinkle rock salt onto the ice and observe the ice melt more rapidly.
Check out the reason that the salt melts the ice more quickly at http://antoine.frostburg.edu/chem/senese/101/solutions/faq/why-salt-melts-ice.shtml. This site has a fun, interactive demonstration when you click “Add Solute” that further demonstrates this principle.
Now help your child drip drops of food coloring onto the top of the ice. The food coloring seeps through the cracks of the ice. You’ve created a beautifully colored, melting ice sculpture. Quick! Snap a picture before it melts away!