Hints on reading body language: shoulder-to-shoulder spacing is generally a bad thing.

My wife and my students will tell you that I'm The Worst at recognizing faces.  Learning students' names is a process fraught with difficulty for me.  A published list of captioned photographs does not help me -- more than once I've been looking straight at a student's photograph and not realized that he's the one standing in front of me.

However, I'm quite good at body language.  I do recognize people by how they walk, how they move.  It's only too bad that these published photo books don't come with video.

I'd suggest that an intuitive feel for body language is an important skill for a physics teacher to develop.  My class is regularly shocked that I seem to know exactly what they're thinking, even when they haven't said a word.  "You're giving me a Look, Mr. Smith," I'll announce.  "The cart must have experienced a force to get it moving, so why didn't I put that on the free body?  Is that your concern?"  Sure, experienced physics teachers know this misconception is out there... but I pinpoint it to the particular student whose forehead wrinkles, whose mouth turns a bit frowny, and who generally looks like my very dear mother listening to Chance the Rapper.

How do I read body language?  How should you?  That I can't exactly explain.  It's not science -- it's art, or perhaps craft.  But it's such an important skill that it's worth trying to share some observations.

Today's thought on body language:  Break up knots of students standing or sitting shoulder-to-shoulder.

I often encounter this phenomenon in the laboratory.  A student who doesn't know exactly what to do sidles in between a working partnership... then more and more join until nine students are assembled around the same lab table.  

They're not working.

Maybe they're commiserating about how "no one" knows how the lab is supposed to work.  Maybe they're making fun of me or of each other.  Maybe they're gossiping.  I'm not sure.  But that gang of too-close-to-each-other students is never, ever productive.

What can you do?  Break it up by any means necessary.

The five-foot rule can be your friend here if they're supposed to be writing things to turn in.  Assigning partnerships, and limiting to three the number of students who are allowed to share data, can provide the original basis for your request for the knot to separate:

"Hey, Mr. Jones, don't forget the five-foot rule... could you please move to that vacant desk?  Thanks!"  "Folks, we don't need five people working with the same setup.  They'll be finished shortly.  Until then, Mr. King and Mr. Garrard, would you please work on the written assignment?  Then when the equipment is available you may use it."  Chances are, students will give you a sheepish look and move away -- problem solved, because everyone will just get to work, finding out that the physics task wasn't as hard as they tried to make each other believe.  

But don't accept any guff.  "Hey, why do I have to move, that's not fair!"  That's when I get upset.  I wasn't initially upset -- and I was careful to control the tone of my voice such that I was making a gentle request, not an angry demand.  But now, after that ridiculous whine, I'm upset.  "I made a reasonable request as to what you are to do in this classroom.  Either comply, or leave."  No need to get into an argument about whether the student was or wasn't goofing off... you won't win that one.  No need to make innumerable rules to enforce about behavior in lab.  It's not hard -- when the teacher politely asks a student to do something reasonable, the student should do so without backtalk.  I believe I was taught that in first grade.*  A high schooler who has difficulty with the concept of compliance has bigger problems than 'what is the speed of the block at the bottom of the incline.'

* I didn't actually learn it until third grade.  But nevertheless.

This battle is worth fighting.  Knots of students drain morale.  Even those who aren't in the knot might be working, but they're working resentfully.  ("Why do I have to do physics while those folks eff around?" they'll think to themselves.)  

So recognize the signs, and break up the critical mass of too-close students before it becomes a problem.  Read the body language.

(Any other body language tips?  Post in the comments.)