Cluster of Things from Inquiry Class:

We are dissecting cow eyes on Monday. I’m excited and nervous. I get to practice dissecting on Thursday.

In class, we discussed several examples of students’ light ray diagrams from the homework. I just displayed using the document camera, and we discussed questions like: What does the diagram seem to be showing in general? Which of our rules are they showing well? Which of our rules are they not showing well? What’s clear? What’s unclear? Why? What questions could a reasonable person ask about this diagram? –> This went a long way toward helping to establish the need for rigor and showing different examples of how one might go about doing this. Students also didn’t seem uncomfortable at all having their work up for discussion. I never said who the diagram was from, but most students spoke up that it was them.

After discussing the examples, I gave students some new situations to diagram. I had them diagram by themselves in consultation with their group, because in this class students don’t get enough individual practice. These diagrams were really great improvement from the homework, and careful diagramming led us easily to have an explanation for why a large hole makes a blurry image. Our idea is that the big hole lets in more rays at various angles, which both “cross at more location”, and cause a bigger “landing area on the back of the screen”, which makes the rays from different points overlap.

We spent the rest of the class investigating lenses, mostly free explore, but I gave them some guidelines for things they should try. This was pretty exciting for many of the group. I love how thoughtful students are about their investigations and questions. They spontaneously try so many things without prompting… like stacking lenses to see what effect that has.. or going back to measure distances, because they are wondering if distance to make it focus when you look through is the same or different than went you cast an image on screen, or realizing that if the lens makes things upside down, then is must somehow make rays cross… and wondering exactly where that is happening, and how… or struggling with how the lens could be so different and yet so similar to a pinhole.

We are in a good place; and I’m proud of them.

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