Purpose of Activity
The objective of this inquiry-based lesson is for students to gain an understanding of how increasing ocean acidity can affect the calcification of marine organisms. During this activity, students: (1) design an experiment to quantify the CaCO₃ concentration of two invertebrate skeletal samples, one that has been soaked in normal seawater and another in a low pH solution, and (2) use critical thinking and discussion to evaluate possible explanations for the difference in the skeletal CaCO₃ compositions. Our lesson focuses on exploring the activity before ocean acidification is introduced to provide a common conceptual framework to engage students. 

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