Sunday, November 27, 2011

On misconceptions

The deeper I dig into how much a child understands a particular idea, the more I  realize persistent misconceptions can be.

We have plenty of places for magical thinking in our culture: horoscopes, good luck charms, religious incantations, and the stock market take up a good chunk of our time. So long as your magic does little harm, and horoscopes and talismans fall into that category, blessed be.

Alas, much of our magical thinking has disastrous consequences. Each morning I grab my wand and recite incantations, hoping to teach science. Before I teach science, I have to unteach the magic.



If you teach young children, and you do not quite grasp something, do not preach it as Gospel. I can teach a child who knows nothing a whole lot more than I can teach a child that knows everything.

We are starting cell energetics this week, the soul of biology. After a few years of doing this, I now know what I must have them "unknow":
  • Plants make food from sunlight.
  • The "stuff" of plants mostly comes from the ground.
  • Plants have no need to respire.
Pretty much all of science gets down to the Conservation of MassEnergy, and in high school biology, where a Newtonian view of the universe is usually sufficient, it gets down to this:


Stuff (matter) is stuff, and energy is energy,
and never the twain shall meet.


These misconceptions run deep, deeper than I realized until the past couple of years. I've gotten better at working through them, but misconceptions are tenacious, and, I think, comforting--children want to grasp the world, and a science teacher running through a laundry list of vocabulary words and biochemical cycles cannot replace the comfort of knowing, even if the knowing is wrong.

This week I'll grab my propane torch, as I have done multiple times, and again show children that water comes from combustion. I'll blow into bromothymol blue solution and again give evidence that CO2 leaves us with each breath.

My stories have to be better than the ones they heard before. My stories have to make as much sense to them as the ones they already believe. My stories must be more true than the ones that define their universe.

My stories need to become their stories, or I've taught them nothing.




Grab David Rudel's books on science myths. Should be mandatory reading for any teacher at any grade that teaches science.

12 comments:

Jenny said...

I have picked up the first of these Science Myths Unmasked books and I am excited to read it. That said, I am beginning to think that it is impossible for me to know enough about all the things I teach (much less all the things my little cherubs ask about) to possibly teach them in ways that won't screw them up for future years. And that's just at first grade! It seems I may need to call upon the networked world in which we live and connect my darling six-year-olds with experts in various areas to answer their questions rather than trying to do so alone.

John T. Spencer said...

"My stories have to make as much sense to them as the ones they already believe."

Some of the best stories make sense, but only through not making sense. They encourage thought and embrace mystery. Light didn't "make sense" until I was able to see the paradox implicit in it.

In third grade, I defined energy as "the movement that changes stuff into other stuff." It was a bad definition, filled with misconceptions, but it beat the one I had to memorize that compared energy to food.

I wish I had learned about energy or atoms or photosynthesis in a way that allowed for mystery, paradox and my own metaphors (sloppy as they may have been).

Instead, I memorized definitions and had to remind myself to use "soil" instead of "dirt" when what I wanted to know was how scraps of veggies had turned into dirt via our compost pile.

Sue VanHattum said...

I just bought the book too. Thanks for the recommendation.

Alan Kay thinks our story-telling abilities get in the way of understanding science, not just because students have learned 'the wrong' stories, but also because stories are too emotionally powerful, and science must depend on observation and repeatability. (I hope I got that right.)

shiftingphases.com said...

Are you reading Brian Frank's blog? His posts on misconceptions in physics have done a lot of good to my misconceptions about learning. You might enjoy this one about using student thinking to help them unlearn a commitment to authority and relearn a commitment to sensibility.

doyle said...

Dear Jenny,

It's impossible for any of us to know everything we're "required" to teach. With a little luck and a lot of hard work, we can teach our lambs how to approach problems.

A network for the peanut crowd questions sounds like a great idea! Sometimes the best answer a child can hear from an adult is "I don;t know. Let's find out!" It's the finding out that matters.


Dear John,

That's about as good a definition of energy flow in chemistry a child is likely to get, and I like it so much I may steal it. It's certainly better than the "energy is the ability to do work," since "work" itself is a tough concept for children (or most anyone else, for that matter).

You've given me another idea as well--I'm going to start a compost pile in my room! As always, thanks for your great ideas!

[I apologize to both you and Jenny for the late responses--I wrote one a couple of days ago, and it got eaten up by the cloud....]

doyle said...

Dear Sue,

Alan Kay is a whole lot smarter than me, but maybe he and I have a different understanding of the word "story"--perhaps mythology is a better word.

Science uses models, of course, and until kids get this, there's little hope in even pretending that science happens in many of our classrooms.

Science does rely on observation and repeatability. That does not preclude an emotional response to the models we create. If it did, there's be far fewer scientists than we have.

doyle said...

Dear shiftingphases,

I am now!

This post germinated from a complex, rational, but wrong view a student held of a biological concept. I thought it got a tad too close to my classroom stuff (which I avoid for privacy reasons), so it became a broader post.

Initially I was pushing the idea that our students make be thinking a whole lot more than we realize, and that is why their misconceptions are so hard to erase--they have an internal logic.

Sue VanHattum said...

>Alan Kay is a whole lot smarter than me, but maybe he and I have a different understanding of the word "story"--perhaps mythology is a better word.

'Whole lot smarter', eh? I think we each use our 'smarts' in our own unique ways. I'm learning more about science from your blog than you might guess.

I don't quite get the story thing, and I'd love to chew on it with you (and Alan).

I wish we could visit in person some day, and discuss all this.

David Rudel said...

A bit of a tangent here...I believe that "energy" is used too much in science explanations. It doesn't really explain anything. It's the ultimate punt.

For example, saying "energy from this battery makes the light glow" is a pretty poor explanation for why a lightbulb hooked into a dc-circuit gives off light.

Similarly, at the high-school level, "This reaction is spontaneous because the change in the Gibb's energy is negative" is about as useful as saying "this reaction is spontaneous because a moose bit my sister."

As a bookkeeping device and abstract principle for solving problems and doing research, it is of course irreplaceable, but as a method of explaining why something happens or doesn't happen, it puts an opaque wall before the learner.

David Rudel said...

Oh, and thanks for the plug for the book, Michael...can't wait to read your actual review of volume 2.

doyle said...

Dear David,

I actually had that conversation with my classes this week. It's a critical conversation.

It helps that every time I mention something about "free energy" we talk about going from one state of conditions to a more (or less) stable state, depending on the situation. I stack up chairs a lot, and knock them down a lot, and if you do this a few thousand times, and the chairs still look exactly the same, students do eventually get that whatever energy is (and I tell them the truth, that I have no idea what energy is) it has something to do with the stability of a given condition.

I showed the children a backwards video this week as well--I asked them how they knew it was backwards. And after the expected "it's obvious," "time only goes this way," etc., a few realized it was a tougher question than they thought at first blush.

And (bless their souls), they started a nice conversation about how they knew time goes forward, and it got to a very nice place--we know the video is backwards because things go more orderly, or things happened that took "too much energy" (which is schoolspeak for going from unstable to stable).

The more I do this, the more I realize how little any of us grasp. We're all stuck in Plato's cave, which is why this is all so much fun.

David Rudel said...

Excellent! My guess is that your students have no idea how fortunate they are to have such a genuine teacher.