Teachers can introduce this activity by asking students what they know about ice: Have you noticed what happens to the water level in a glass of ice water as the ice melts? Where do they predict water will flow once the ice melts in this experiment? At the end of the activity, ask students how they interpret the results (graph) in terms of the actual phenomenon of sea level rise. Which contributes to rising sea levels: sea ice or land ice?
Encourage students to think about the real land/sea environment. Where would water flow as land ice melts? Would land ice or sea ice melt faster? Is global ice melting due to warming of air, land, seawater, or all of the above? Variables to consider include effects of heating of continental materials (soil and solid rock) versus water and air, flow of melting land ice vertically below ground versus horizontally into oceans, and whether land ice or sea ice is more abundant globally.
Students can think like scientists by discussing how well this model represents the sea and land in real life. What might be missing and what could be simplified to improve our understanding of what the model represents? One example of improving this experimental model would be for participants to have control of the temperature around the model. Increasing the temperature around the model throughout the course of the experiment could help represent climate change, and would produce a different rate of sea level rise.
This Snack is also a great opportunity to have students think about data collection and interpretation. How would they report their findings to others who did not conduct the experiment? How could this be explained to make it clear to others? What do the results mean for understanding causes of sea level rise? What does a graph of a horizontal line mean as an observation? How would changing a variable in the model affect the trend in the data (examples: slope of line changes, all values decrease/increase equally)?
For younger students, this could be set up as a demonstration or station, which a class can observe over the course of a school day, marking the sides of the containers with the water levels every hour.