MS-ESS2-1 Develop a model to describe the cycling of Earth's materials and the flow of energy that drives this process.
Clarification Statement: Emphasis is on the processes of melting, crystallization, weathering, deformation, and sedimentation, which act together to form minerals and rocks through the cycling of Earth’s materials.
Assessment Boundary: Assessment does not include the identification and naming of minerals.
This resource appears to be designed to build towards this performance expectation, though the resource developer has not explicitly stated so.
Comments about Including the Performance Expectation
This activity serves as an aid in understanding one part of the water cycle – precipitation. This activity should be one of several that a student engages in. Other activities should include transpiration, runoff, condensation, and evaporation. Although the focus of the activity is precipitation, it should be noted that condensation also occurs. When doing this activity ask questions such as, Where did the water that is dripping from the bag come from? Students may have the misconception that the water comes from the bag of melting ice. The bag could be weighed before and after to show water isn’t leaving the bag. Students should think about the changes in energy the water molecules undergo. Why does the water evaporate? What causes the water to condense or become a liquid again? Why does water drip off the bag? Questions and discussions about how this activity relates to cloud formation and eventually rain should also be included so students can start relating these processes to the water cycle. Students are not developing a model for precipitation, rather they are replicating an already established model. However, if students are asked to draw and describe what is happening to water molecules for evaporation, condensation, and precipitation to occur, they would be developing a model. There would need to be a discussion with students about the role of gravity and then how this model serves to represent how precipitation forms in clouds – water first has to condense and enough needs to accumulate so it can fall. This activity itself doesn’t include the role of the sun and its energy in driving this part of the hydrologic cycle but should be a part of the discussion.