Models are by nature interconnected.
We place the scientific and more broadly cognitive practice of modeling at the center of our work. As we puzzle over phenomena in our world and ask questions about them, we develop models that allow us to connect ideas, answer our questions, and ultimately explain the phenomena we've been trying to understand. Not only do models provide a vehicle for understanding within a single unit of instruction, but they also allow us to make connections across units and topics. Models in science are by their nature inextricably interconnected. Working to really understand Natural Selection, for example, ultimately leads to an exploration of Inheritance. Exploring a model for Growth and Development draws not only upon ideas about Inheritance, but also from an exploration of environmental effects on phenotype and the allocation of matter and energy in organisms. Ideas in science do not stand alone but are intimately connected, often in complex ways. Our understanding of science, then, comes through iterative generation of, integration of, addition to and re-generation of models. As we develop new model ideas, they inform other ideas we already hold and help us to better explain the phenomena we observe in the natural world. (Read more about models and modeling in the MBER Essentials as well as our way of tracking coherence in the classroom, the PQM Triangle.)
This MBER Living Earth sequence draws upon the interconnectedness of models...
while simultaneously recognizing that time (i.e. a school year) is linear.
Our first challenge as a team was to thoughtfully integrate earth science standards into an already-packed year of biology we had developed through the MBER-Biology Project. As a first pass, we considered those standards outlined in California's "Three-Course" high school model for NGSS alignment. In working through those high-level outlines, we made a series of decisions regarding not so much which performance expectations to include, but which earth science models to include in our exploration of high school biology. (This may mean that you will need to check your district requirements against our own scope and sequence. Please see the pages on Alignment and MBER for specific information.)
Our second challenge was to “linearize” the sequence while recognizing the web-like relationship among the ideas. As you can see in the sequence map, our solution was to visualize the year as a wheel or clock of sorts. Around the wheel itself, you'll find the units in the order we've prescribed. The "wheel" itself, however, reveals a different perspective of how the year is coherently designed: beyond the typical exploration of the biosphere (the typical domain of biology and the life sciences), this curriculum makes explicit connections to the Earth's other component "spheres"--the geosphere, the hydrosphere, and the atmosphere. The "spokes" for each unit, then, represent how deeply they conceptually explore the other spheres or domains of our planet. You'll notice that some units explore mostly one sphere--for example, the formation of Earth model lies wholly in the realm of the center geosphere and many of the biology units retain a more traditional exploration of life in the biosphere. But there are other units that integrate across the spheres. (See especially the Oxygen unit, the two ecology units, and the final unit on evolution.) By "reading the spokes" you can see how individual units call on us to make connections across the spheres. Superimposed on top of Earth's four major spheres is the outermost, the "anthrosphere".
Though humans are solidly an integrated member species of the biosphere, the anthrosphere depicted here represents those unique ways in which humans have changed the planet--some of which provide challenges, and others which provide solutions. The explicit layering of this additional sphere allows us to attend to the overarching theme of human impacts in this Living Earth curricular year. You'll notice that we start the year with questions about the role of humans and end it with a reflection on what we've learned about the power of humans to both harm and heal our unique planet.
Ideas building on ideas... models building on models.
The last aspect of the diagram to consider are the questions that surround it. These speak to broad themes in the sequence. For example, the launching units, shown in the yellow of earth science, ask us to explore the origins of Earth, with particular attention to the non-living pieces. Purple units pull us into deeper questions about the origins and evolution of life, a central theme in biology that sets up the exploration of other questions. In looking at the color legend, you can see how the questions surrounding the diagram correspond to broad themes in organismal biology, genetics, ecology, etc. Though these themes and their corresponding questions are somewhat clustered along the edge of the wheel (e.g. all of the red units are together), each series of units is explored through the lens of what we've already figured out in prior units. Exploring the Carbon Cycle (a green, "ecology" unit) directly builds on our understanding of how carbon moves within organisms, models we built through exploration of organismal biology phenomena in the red units. In this way, the diagram depicts yet another layer of coherence.
We hope this diagram helps you to make sense of connections across the year. We do not expect that you will use it with your students, though you are welcome to do so. We designed it for you, for students, we attend to coherence on a daily basis, helping them navigate connections between what they did yesterday and what they are doing now through attention to anchoring phenomena, driving questions, and the development and revision of models that connect across the year.
Coherence has been a driving principle in the design of this sequence. We strongly believe students learn best by building their own understanding and returning to some key ideas again and again.
Thanks for taking the time to read. You'll find more information embedded in the resources themselves (PowerPoints, teacher guides, etc.) and in the MBER Essentials here on the website.