When we start investigating a new topic or component, I often ask students to make inferences or ask questions by applying our existing model to the new idea.  For example, after introducing an inductor as a length of coiled wire and taking some measurements, I expect students to infer that the inductor has very little voltage across it because wires typically have low resistance.  However, for every new topic, some students will assume that their current knowledge doesn’t relate to the new idea at all.  Although the model is full of ideas about voltage and current and resistance and wires, “the model doesn’t have anything in it about inductors.”

There are a few catchphrases that damage my calm, and this is one of them.  I was discussing it with my partner’s daughter, who’s a senior in high school, and often able to provide insight into my students’ thinking.  I was complaining that students seem to treat the model (of circuit behaviour knowledge we’ve acquired so far) like their baby, fiercely defending it against all “threats,” and that I was trying to convince them to have some distance, to allow for the possibility that we might have to change the model based on new information, and not to take it so personally.  She had a better idea: that they should indeed continue to treat the model like a baby — a baby who will grow and change and isn’t achieving its maximum potential with helicopter parents hovering around preventing it from trying anything new.

The next time I heard the offending phrase, I was ready with “How do you expect a baby model to grow up into a big strong model, unless you feed it lots of nutritious new experiences?

It worked.  The students laughed and relaxed a bit.  They also started extending their existing knowledge.  And I relaxed too — secure in the knowledge that I was ready for the next opportunity to talk about “growth mindset for the model.”