Does the scientific practice of modeling actually support students in making thinking visible? Middle school teachers can build from the work of 12 K–8 teachers who wanted to learn how the practice of modeling is developed across grades and analyze how those skills end up looking in middle school. They gave their students the same phenomenon and prompts, tried them out with their students, collected models to compare them, and then came together across two years to discuss modeling. All students across the grades showed similarities in the models, both in terms of how they presented ideas and the scientific ideas. Many middle school models looked similar to those in early grades, and although middle school students showed particles of air in the models, the usefulness of the particles to explain the phenomenon was almost always unclear from the models alone. Implications for assessment of middle school students include discussing models with students to assess their knowledge and including fewer student scaffolds at the onset.

A valuable framework for promoting sensemaking includes the convergence of two independent ideas: (1) the focus of modern education on teaching for understanding and transfer, and (2) a purposeful sequence of instruction with those ends in mind. In essence, the sensemaking framework intends to help educators identify the big ideas we want students to understand at a deep level (e.g., construct evidence-based claims from firsthand experiences) to transfer their learning to new situations. This conception is perfectly aligned with the NGSS emphasis on teaching science through the conceptual lenses of Core Ideas (called Disciplinary Core Ideas [DCIs], Practices (Called Science and Engineering Practices [SEPs]) and Crosscutting Concepts (CCs) rather than fixating on factual information only. In addition, this view aligns with the four NSTA's critical attributes that including phenomena, science and engineering practices, student ideas, and science ideas (see https://www.nsta.org/sensemaking). The explore-before-explain instruction sequence helps teachers prioritize students constructing evidence-based claims in the sensemaking framework. What follows is a description of the four key planning considerations for sensemaking and how explore-before-explain teaching plays out in practice for teaching middle school students about thermal energy transfer.

Although the NGSS has helped teachers conceptualize teaching science in a more integrated way, effectively scaffolding students’ thinking within and across lessons can still be a challenge for any middle school science teacher. Thinking about the curriculum structure can be useful for scaffolding across lessons (Figure 1). While many curriculum structures exist (Posner, 2003), some structures are better at providing the teacher opportunities to promote sensemaking across lessons and units. For example, a spiral curriculum is where relevant prior concepts are revisited in order to connect them to new concepts. Revisiting concepts is meant to deepen students’ knowledge rather than merely repeating previous content (Harden, 1999). In our state, each middle grade has NGSS standards for life, physical, and earth/space science. We’ve found the spiral curriculum was useful to help students see connections across science disciplines. Our light unit (Table 1) comes before our unit on space science (Authors, 2018). In this article, we demonstrate how we scaffold students’ learning to help students make connections between lessons about light (MS-PS4-2) and gravity (partially addressing MS-ESS1-2). We use these experiences to help students understand gravitational lensing