In this Model-Eliciting Activity (MEA), students work in collaborative learning groups to classify pH values. Students are faced with a problem of correcting possible affects of contaminating pollution. Scenarios of a problem statement help students apply factors to water resources in real world events. They recognize and explain that a scientific theory is well-supported and widely accepted explanation of nature and not simply a claim posed by an individual. Students may prove their proposal by performing a pH wet lab with common kitchen solutions. pH - The Power of Hydrogen Ions implies that the "power of health is in balance" with balanced "Hydrogen Ions." Life exists inside a certain range of pH values.

Model Eliciting Activities, MEAs, are open-ended, interdisciplinary problem-solving activities that are meant to reveal students’ thinking about the concepts embedded in realistic situations. MEAs resemble engineering problems and encourage students to create solutions in the form of mathematical and scientific models. Students work in teams to apply their knowledge of science and mathematics to solve an open-ended problem while considering constraints and tradeoffs. Students integrate their ELA skills into MEAs as they are asked to clearly document their thought processes. MEAs follow a problem-based, student-centered approach to learning, where students are encouraged to grapple with the problem while the teacher acts as a facilitator. To learn more about MEAs visit: https://www.cpalms.org/cpalms/mea.aspx