Grade level
Developing and using models
Planning and carrying out investigations
Engaging in argument from evidence
Cause and Effect
Energy and Matter
ESS2.A: Earth Materials and Systems
ESS2.C: The Roles of Water in Earth’s Surface Processes
ESS3.A: Natural Resources
Students created sandcastles using slightly wet sand. Using a paper fan, students were instructed to create a gentle wind that they blew toward their castle and draw in their science journals how the wind affected the sand. Students shared the outcome of their sandcastle investigation. They had to make sandcastles using slightly wet sand. Next, with a new sandcastle, they used droppers to slowly drop 8 drops of water on it. Once more, they had to draw how the water affected their castle. This was done to observe how water affects different materials, and how it behaves on sand.
During the investigation, students noticed the more powerful impact of the water (Samples A & C) on the sand compared to the wind (Samples B & D) in this set-up. Students recognized that the water made holes in the sand (A & C) and that it moved the sand in quite destructive ways. Some students also had initial ideas about absorption (Sample A) as they talked about the dirt “drying out” the water. Those talking about their observations of sand mentioned how the wind only affected grains of sand that were loose or on the outside of the structure, leading to far fewer structural changes. In further discussion, students predicted that had they continued dropping water, the sandcastles would have broken down even more. They could see the material, in this case sand, moving in the water downward, and instead of pooling, they could see the dirt absorbing the amount of water they were instructed to use.
