Paint pictures with the mixture. The water will evaporate leaving the colored sand. Using 2 clear cups, fill each with water. In one cup, stir in 3 T. of salt. Label the cups A and B. Ask students to predict what will happen when you place an egg in cup A. Place the egg in carefully.
Salt adds density to the water so objects float.
Put sugar cubes in a clear jar. Have students take turns shaking the jar then observe what happened to the cube. Explain that is what happens when rocks get tumbled together in rivers or waterfalls, or by the wind. In a large pot, bring the ocean to a boil. Toss in the seaweed and snails.