Student preconceptions are one of the greatest challenges we face as science teachers. This Predict, Explain, Observe, and Explain (PEOE) activity challenges students’ preconceived notions about why matter floats or sinks when placed in a liquid. The idea behind this model is to do a demonstration that first confirms students’ conceptions followed by a second, similar demonstration that provides discrepant information creating cognitive dissonance. Learning happens as students are forced to modify their conceptions so that their view of how things work is not in conflict with what they are seeing.
Ideas For Use
The main idea being taught in this lesson is that the buoyant force of a fluid is directly related to the differences in the densities of the materials. The ice cube floats instead of sinks because its density is slightly less than that of oil. After completing this demonstration, there are several questions that you may need to explore with your students.
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Scientific habits of mind
|Intended User Role:||Curriculum Supervisor, Middle-Level Educator, Teacher
|Educational Issues:||Classroom management, Curriculum, Inquiry learning, Instructional materials, Teacher content knowledge, Teacher preparation, Teaching strategies
|Requirements:||Requires Adobe Acrobat Reader
State Standards Correlation
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