Purpose
[stextbox id = “info”] To assess growth in students’ understanding of the particle model of matter and how the model explains dissolving salt in water.[/stextbox]
Description
[stextbox id = “info”] Revisit the super strong glasses scenario from Student Experience 2. Ask students to again draw what they would see in the glass of water, both before and after the salt is added, if they had super strong glasses using this task sheet. After they have completed their drawings, have students make comparisons to their original pictures. [Task instructions for pilot teachers.] [/stextbox]Questions to Ask Students
[stextbox id = “info”]- Describe your drawing. What does each part represent?
- How is this drawing different from your first one? What have you learned that affected your new drawing?
- How does your drawing explain what happens when salt is stirred into a glass of water?
- How does your drawing compare to the computer simulations we watched?
Student Thinking
[stextbox id = “info”] Students’ drawings should show evidence of particle thinking by including water particles and salt particles. If they do not, revisiting the simulation might help.[/stextbox]
Implementation Tip
[stextbox id = “info”]Challenge students to add more detail than they included in their first drawing, even those students who included particles the first time.
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