Grade level
Planning and carrying out investigations
Constructing explanations (for science) and designing solutions (for engineering)
Engaging in argument from evidence
Cause and Effect
PS1.A: Structure and Properties of Matter
LS2.B: Cycles of Matter and Energy Transfer in Ecosystems
Students were given ice cubes that contained glitter and other small particles as a means to model the movement of water and other particles as it melted on different surfaces. The ice cubes melted in the sun on two different surfaces (watercolor paper and plastic plates) and students were asked to observe what happened to water and what happened to the glitter (sediment). Students reflected on their ice cube observations by answering a set of questions, first as a whole class and then in their journals. The questions focused on: 1) How did the melted ice behave differently on the two surfaces being tested, plastic and watercolor paper? and 2) What might the glitter and corn starch—used to make the ice cubes—represent as a model of the real world?
Students paid close attention to their investigation set-up and watched as the ice cube melted over time. Their drawings showed that they saw a difference between how the water interacted differently with different materials, in particular that the water was absorbed by the watercolor paper and left standing on the plastic plates (Samples A and B). Across the samples, many students recognized that the glitter represented dirt and other particles in the water (Samples A, B, and C). One student talked about how the glitter gathered at different spots on the paper and was not evenly distributed and this raised a question for further investigation about why the glitter was only found at the edges (Sample E). However, some teachers noticed that students had difficulty understanding that the investigation materials represented a model of what happens in the real world, prompting a desire to engage in additional practice and discussion about how scientists make models to represent real world situations, as evidenced by the student’s literal drawing in Sample C and some of the students’ comments in Sample E and F.
