A year ago, I was one of those people who cut students off to correct them if they said that voltage went “through” something.  It was unbearable to imagine them reinforcing that idea every time they said it.

This, it turns out, is my misconception about learning.  Brian Frank advocates asking “generative questions” to our students — and to ourselves.  His questioning approach was doing a great job of reorganizing the inside of my brain, which I took as proof that it worked.  So this September, I tried it with my students.

Instead of using videos and models and demos and Prezis to help students understand the structure of an atom, I tried to find a generative question.  The best one I could come up with was “What’s really happening when you push two magnets together?”

Then, I took some advice he has for new TAs: write everything down.  It forces you to pay close attention, makes it harder to interrupt, and facing the board means the students won’t see you cringe.  (Joking.  Ok, partly joking.  It makes it harder for them to get distracted with scanning your face for signs of wrongness.) Some of the results are on the whiteboard above.

My Reactions

It was really hard to write things that I knew were false.  It was especially hard if no one was disagreeing with it.  It was especially hard if it clearly contradicted something else they had just said. It was especially hard if I knew that that idea would be a stumbling block for months, for some students.

Why would a reasonable teacher have these reactions?

Ok, I’m not an authoritarian tyrant in the classroom.  (Mostly).  I preach celebrating mistakes and “trying something” and don’t worry, you can improve it in your reassessment.  Why was I reacting this way?  When I really asked myself, I ended up at the fall of modern civilization.  No, seriously.  Illogical inferences, lack of awareness of contradictions, and failure to question authority are ingredients of poor quality reasoning that I fear are at the root of political corruption, social injustice and, you know, tooth decay.

That was helpful.  I realized I had to get over my delusions of grandeur.  See?  My misconceptions were already helping me.  (Although, only because I asked myself why I held them.  And I only noticed them because Brian asked a generative question.)

There are other reasons I was uncomfortable, of course.  I know how hard it is for students to let go of things they’ve “always known,” and it’s upsetting to me to imagine making that process any harder.  But I realized I had to do something different when my second-year students reflected back on the atomic structure they had learned.  They found themselves wondering what the difference was between an atom being “balanced” and a substance being “pure.”  (Some of them also told me that there was air between the nucleus and the valence shells).

I also know that my students come to me with an expectation that everything the teacher writes on the board is “true,” and should be copied into one’s own notes.  It will then be available forever, as a bank of certainty when they feel lost.  I need to help them change that perception, or else my attempts to honour their thinking will be horrible betrayals of their trust. I need to help them change that perception anyway… because unless they question me, they’ll never be completely sure of themselves.

How I coped

So, I wrote everything down.  I made concessions to my fears, though.  I tried to remember to put question marks at the end of every sentence.  I think this has played out in a useful way.  It has helped us think of all ideas, including the ones quoted straight out of textbooks, as open to question.

I asked lots of questions, mostly seeking out clarity and contradictions (“what do you mean by ‘positive,’ exactly?”   Or “We’ve also got ‘vacuum’ written down.  Are you contradicting that or supporting it?”).  I noticed myself making choices about whether to address the question to the speaker or to the room.  Sometimes it seemed helpful to gather a number of statements about an idea (especially if they were contradictory) before going back and teasing out the meaning of each word.  I guess I was hoping people would feel less singled out (and others in the room would feel more welcome to take part) if I let a few ideas go by before returning to a particular word.

When I ran out of things to clarify, I asked questions like “how?” “why?”  “how much?”  and “where?”

Some examples of what we came up with:

  •  What about space — does it have atoms?
  •  Is space what’s in between atoms?  How do we know?
  •  Can atoms touch?
  •  Can protons move?
  •  We think protons are bigger than electrons because they weigh more (how do we know?)
  •  Maybe at the smallest level, things can’t be broken down into smaller parts, so saying that something is made out of energy and saying that it IS energy might be the same
  •  Is there friction between atoms?
  •  We were able to magnetize pliers but not the metal discs from the magnet kit — even though they stick to magnets.  Why?
  •  If you use a magnet to magnetize something, does the original magnet get weaker?
  •  Is there any difference in the magnetic properties of an electromagnet or a regular magnet?
  •  We think magnets can be manufactured, because the cute fuzzy carrot on your fridge wasn’t mined out of the ground. How are magnets manufactured?  How do they make them permanent?
  •  We think magnets can get weaker over time, because things fall off the fridge.  What is happening to them?  Does it relate to how much you use it?

Then I gave everyone a pile of magnets and asked them to test as many of our ideas as they could.

How the students coped

The students did really well with this.  They fired off questions and contradictory ideas.  When given a pile of magnets, they tried lots of things, documented them, and were proud to report back what they found.  Interestingly, most of their findings were not related to the ideas we had discussed.  (I’m not sure whether that means they don’t know how to design an experiment, or if they just got distracted with things that seemed more interesting).  I wrote down the findings from the report-backs, and class ended.

Follow up

I typed up the questions we had generated and handed them out at our next class meeting, in the shop.  This was met with much appreciation (unexpectedly), and I realized that one of the things that stresses my students out about freewheeling conversations is that the more they participate, the less time they have for “taking good notes.”  (I’d rather that they talk and I be the secretary, than that I talk and that they be dozens of secretaries).  I reviewed the ideas we had tested, which left a big pile of questions we hadn’t tested.  I asked everyone to find one idea about each question, using a total of three sources: at least one book, at least one website, one of their choice (this was a sneaky way for me to introduce the ideas of “technical reading,” but the popular favourite was this video featuring physicists Longair, Krauss, and Kaku).  They had their own textbooks (algebra-based, intro level), of course, but I also brought in some calculus-based university physics texts and some pop science books.  Then I sat down, and a room full of first-week trade school students spent two hours poring over the details of subatomic physics.

What next?

We’ve gone through another round of thinking and questioning.  The questions keep getting more relevant and profound (another post).  Next day, we’ll take what we know and try to apply it to electricity.

My question

Two students read Brian Greene and Michio Kaku for fun.  They’re full of “facts” about subatomic particles, but no fewer misconceptions (air between the nucleus and the electrons; magnetism and electricity are the same thing; confusing ions with isotopes).  The problem is that they’re disruptive (shouting out answers before I can ask someone to respond; having side conversations while others are talking), and I think it’s because they’re bored.  I think they see this process as beneath them, even though they’ve both had “aha” moments.  I’m working on addressing this in a few ways.  One is by using flash card questions using Andy Rundquist’s confidence system so that they at least feel that they’ve told me “I know this already.”  Another is by creating opportunities for them to seek out the resources that interest them (above level texts, Internet, etc.).  I also need to enlist them in the more difficult task of figuring out “why would a reasonable person think this.”  What I want them to sort out is that there is a difference between the logical judgement needed for evaluating whether an idea is reasonable, and the intellectual humility needed for inferring why someone thinks something.  I need the word “reasonable” in the formulation because the answer to “why would someone think this” is likely to be “because they’re stupid.”  (Check the comments of this post for a great discussion of this question).  If anyone has any suggestions, bring em on…


In answer to whether protons can move, one student dropped a pencil on his desk and said, “those ones can” (I’ve probably said “protons don’t move” a thousand times without paying attention to this).  In answer to whether electrons are much smaller than protons, one student pointed out that they’re drawn the same size in the book (I hadn’t noticed).   I’m learning to stop listening for their misconceptions and start listening for mine.