The NGSS are all about Phenomenon-Based Learning, but it can be challenging to find good phenomena that can generate the kinds of essential questions that motivate student learning. These questions need to be broad enough to be able to encompass all of the specific parts of the three dimensions (content, practices, and crosscutting concepts) that you want to cover in your specific bundle of topics, but also be engaging for the students, which often means being relevant. Well, there are fewer things more relevant and engaging than human impacts. Why is it that only 4% of the mass of all land mammals on Earth are wild (the rest are humans, 36%, and our livestock, 60%)? How is it that humans now cause erosion more than 6x faster than all natural causes combined? How have humans managed to raise global temperatures? The California Integrated High School model, with its three courses of Biology and the Living World, Chemistry in the Earth System, and Physics in the Universe, provide many good examples of human impacts as phenomena. For example, if you are teaching about chemical reactions, use the combustion of fossil fuels as your phenomenon. If you are teaching about acids and bases, use ocean acidification and coral bleaching as your phenomena. However, whenever possible, pose the essential questions in the framework of finding solutions to human impacts, and not on the impacts themselves. The specific wording of several of the NGSS performance expectations in Earth and space sciences focuses on finding ways to mitigate or reduce human impacts. Keeping that engineering design-based focus keeps students hopeful and empowered in the face of the large environmental challenges that their generation will face.
