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Purpose
[stextbox id = “info”]To assess growth in students’ understanding of the particle model of matter and how the model explains conservation of weight during phase change.
[/stextbox]Description
[stextbox id = “info”]Revisit the super strong glasses scenario from Student Experience 1. Using this task sheet [2], have students again draw what they would see in the ice cube and liquid if they had super strong glasses [3], more powerful than the most powerful microscope. [Task instructions for pilot teachers. [4]] [/stextbox]
Questions to Ask Students
[stextbox id = “info”]- Describe what’s in your drawing. What does each part represent?
- How is this drawing different from your last one?
- How is this drawing different from your first one (the ice cube in the lunchbox)?
- How could you use what you just drew to explain your prediction about what happened to the weight of the ice cube after it melted?
Student Thinking
[stextbox id = “info”]The simulation may not convince all students that matter is made of particles. Look carefully at students’ new drawings to see if they have kept some of their earlier ideas.
- Some students may still believe that matter (in this case water) is continuous rather than made up of particles (in this case water molecules) (Benson et al., 1993; Nakhleh & Samarapungavan, 1999; Renström et al., 1990; Séré, 1986) [5]. These students are likely not to include water particles, or any other kind of particles, in their drawings.
- Students may also still think particles are IN substances (water particles in a body of water) (Beerenwinkel, Parchmann, & Gräsel, 2011; Lee et al., 1993; Novick & Nussbaum, 1978, 1981) [5], which should also be evident in their drawings.
- Students may still think that there is NO space between particles (Benson et al., 1993; Özmen, 2011; Özmen & Kenan, 2007) [5].
- Students may still not understand that the particles are constantly moving, even in ice (Herrmann-Abell & DeBoer, 2011; Lee et al., 1993) [5].
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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