In this activity, students observe and compare the features of a solution and a mixture.
What happens when we combine a liquid and a solid? When a solid dissolves, it seems to disappear. The dissolved solid is still there; we just can't see it.
Sugar is and example of a solid that breaks down into tiny pieces, and dissolves in water. When the sugar is spread completely throughout the water, we call this a solution.
Not everything dissolves, however. Rocks and sand do not dissolve in water—they sink to the bottom. We call this a mixture.
These activities are part of Science World’s Big Science For Little Hands program. They were developed and tested with preschool and kindergarten educators. Some of the activities are done in stations.
Mysterious Mixtures PDF from Big Science For Little Hands.