Re: [Phys-l] Student Misconceptions

[John Denker <jsd@av8n.com>]

On 09/28/2011 12:15 PM, andre adler wrote:
> Is there a single volume a physics teacher can refer to that
> contains/discusses common student misconceptions in physics, as
> revealed by PER?  I know that there are many articles documenting and
> studying them, but they seemed to be scattered over the years and over
> the journals. The desire is to use this as part of course preparation.

My advice is:  Don't go there!

1) The fact is, students have more misconceptions than 
 anyone could possibly imagine ... but if you've made 
 it this far, you already know that.

2) There are so many misconceptions that it would be
 impossible to list them all, let alone analyze them.

3) It is OK to talk about this-or-that misconception in
 this forum, but talking about misconceptions in front
 of students is at least as likely to reinforce the
 misconception as to dispel it.

4) As a consequence of the above, the best policy, with
 isolated exceptions, is to teach the correct concepts
 and move on.  "The light shines in the darkness, and
 the darkness cannot overcome it."

 Imagine a very narrow path through a vast swamp.  You
 want to stay on the path.  If you pick a random point
 in the swamp, there is a 99.99999% chance you don't want
 to be in that place, or even talk about that place.

 On rare occasions, as you lead students along the path,
 you might want to point out something nasty that is
 just next to the path, so they can recognize it and
 avoid it ... but mostly it is easier to recognize the
 path than to recognize the pitfalls.  This is the Anna
 Karenina principle:  All happy students are alike, but
 every unhappy student is unhappy in his own way, and
 is going to find some weird misconception that you
 never dreamed of.

5) The real cases worth worrying about are the ones that
 are exceptionally prevalent and exceptionally pernicious.
 The classic example concerns the washed-out bridge.  It
 is worth putting up a "Bridge Out" sign and maybe a
 barrier and (better) detailed detour signs, because
 people who haven't been warned are going to assume the
 bridge is OK, with fatal consequences.

 There are very few of these that show up in the intro
 physics classroom.  By way of contrast, in the research 
 lab you might have high-power invisible lasers, high 
 voltages, toxic chemicals, et cetera, and we would be 
 having a different conversation.

6) I'm not so much worried about the misconceptions that
 the students bring to class as the misconceptions that
 the teacher and the textbook author bring to class.

 Having not taken my own advice, I made a modest list.
 You've been warned:
   http://www.av8n.com/physics/misconceptions.htm

7) Reading the PER literature is definitely a source of 
 misconceptions.  I don't mean you will get a tidy list
 of misconceptions, I mean you will suffer from more
 misconceptions than you started with.

 For example, the book 
     Arons, 
     _Teaching Introductory Physics_ 
 is – unintentionally – an extensive compendium of bad 
 pedagogy and wrong physics.   For a detailed review, 
 including a list of some of the misconceptions propagated 
 and/or introduced by this book, see
    http://www.av8n.com/physics/arons-1996.htm