prediction. A theory is why something happened. It’s not just a guess or a prediction.”

Caleb: “I know what a theory is. A theory is like ‘all wood floats.’ That means all wood has to float or else your theory is wrong.”

Mr. Wilson: “Okay, so let me see if I’ve got what you’re saying. You’re saying that ‘all wood floats’ is a theory?”

Caleb: “Yep, a theory that’s been proven right.”

Mr. Wilson: “Does that tell me why wood floats though?”

Caleb: “Uh, not really.”

Mr. Wilson: “Okay, so can you give me an example? Let’s take wood. Some of us have seen in our experiments that wood floats. We have evidence that wood floats. But why does wood float? What makes it float? Can you give us a theory?”

Caleb: “My theory is that you can trap air underneath the wood.”

[Mr. Wilson notes Caleb’s theory on the theory chart.]

Elinor: “Your theory isn’t really [she looks at the question chart] intelligible to me. I don’t completely get what you mean by ‘wood traps air underneath it.’ [She looks at the question chart again.] Actually, it’s not really plausible to me either. I mean how would wood trap air underneath it? It’s not like a cup or anything, so how would wood do that? Do you have any evidence to support that theory? Did you see air bubbles? Or did you just come up with that theory from your mind?”

Caleb: [Smiling] “I just sort of flashed on it. But I like it. I mean it might have something to do with air.”

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