The Homeostasis module supports science reading and introduces the use of texts as tools for constructing, revising and defending explanatory models of phenomena that relate to disciplinary core ideas in Biology. The Homeostasis Investigation focuses on two examples of homeostasis in a human body: the balance of sodium and sugar concentrations in blood serum. In line with our design principles, the module includes multiple texts of multiple modalities (e.g. clinical studies of hypernatremic patients, news stories, diagrams from Biology textbooks, and texts from the New York Times and The New Yorker). The module includes explicit modeling and explanation tasks, peer review with scientific argumentation for the modeling and explanations tasks. Each of these tasks requires that students use information from texts in the text set to develop, refine, and apply explanatory models to related phenomena around the disciplinary core idea of Homeostasis.

We collaborated with two high school biology teachers to select human homeostasis as a topic for this module, based on the college readiness frameworks (Annenberg Institute for School Reform et al., 2014), the Common Core State Standards (Council of Chief State School Officers, 2010), the Chicago Public School Biology content frameworks and the Next Generation Science Standards (NGSS Lead States, 2013). The module focus is on 2 cases that exemplify how feedback within and between organ systems maintains homeostasis in the human body. The first half of the module focuses the maintenance of sodium ion levels in the blood – both cases of when the balance is in maintained and when it is disrupted (hypo- and hypernatremia). The second half of the module focuses on how the body maintains appropriate blood sugar levels, and cases when this balance is disrupted (e.g. Diabetes). The Homeostasis module text set includes both texts that are specific to mechanisms that govern salt and sugar balance, as well as more generalized texts that describe on the principles of human homeostasis. The Homeostasis Module Interactive Notebook includes integrated routines, scaffolds, and tasks.  Inquiry questions support student engagement with the phenomena. Notetakers support students in identifying and reasoning about evidence in the texts; and modeling and argumentation tasks to engage students in these science practices. An annotated teacher guide provides support for implementation.