Student models improved significantly in their detail over the course of the unit. Final models were more detailed, colorful, and included vocabulary words and arrows. Sample A shows the most common representations including the causal impact of the sun’s heat on the melting of ice, which then, due to gravity, results in water flowing downhill. This water then evaporates and results in the formation of clouds from water vapor and in this sample we see a connection made between the movement of water and the dry and wet regions. Sample B reflects less connected thinking of these different pieces with representations of evaporation and water movement, but not connected in a causal story. Sample B also shows a misconception about the nature of fresh and saltwater.

Sample C shows a detailed description of the generic process of the water cycle, which is common among many models. Sample D also shows that students recognized a variety of ways in which water moves through the geosphere. However, few models, like Sample E, make a connection between water abundant and water poor environments and how the water could directly move between these locations.