through questions, discussion, and observations for much of the class period, the students were ready to summarize their class experience and its implications for the meaning of force. One said: “Since the table bent, like a stiff spring, all things had to deform some to support the book. Deformation was one sort of evidence we could look for when we considered forces.” Another added, “That meant we could give the same explanation [involving an upward force] across several different ‘at rest’ systems.” Another said: “That also meant we didn’t need to worry about whether the supporting object was alive, awake, active, or passive. We could just focus on the observable evidence of deformation, although sometimes we might need more sensitive instruments [like a light lever] to detect the deformation.” Mr. Hull pointed out that that was one of the “rules” of science: “If a simple, consistent explanation would work across several situations, then use the simpler explanation rather than needing to rely on use of different explanations depending on some non-observable characteristic like whether the object was actively or passively supporting the book.” Mr. Hull further validated the work of the students, suggesting “that force could have been defined by incorporating the active/passive distinction, but for reasons like consistency and tying our ideas to observable evidence, the scientists’ conception of force is more like the one our class has derived. Also, we now know that this conception has worked well for scientists for a long time. Like scientists, we will take our present idea of force as tentative and use it until new evidence suggests we might need to revise it.”
The inquiry does not end here. In subsequent lessons focusing on forces on moving objects, students further develop their understanding of force and of the nature and processes of science. The preceding lesson is but one short inquiry allowing students to begin to understand the complex ideas that science has developed related to force and motion.
This example represents one lesson conducted in a single class period. Nevertheless, it demonstrates how a teacher can seamlessly interweave science subject matter, inquiry abilities, and understandings of scientific inquiry.
Learning Outcomes. Mr. Hull used three learning outcomes from his local school district curriculum and state standards to help him plan what and how to teach. Each of these three outcomes is also found in the National Science Education Standards. First, his lesson provided opportunities for his students to understand and apply the concept from physics of