Thursday, August 14, 2008

Why I Teach: modeling atoms

I teach physical science. Officially it's Precollege Preparatory Physical Science now, was Integrated Science 1 last year, and Career Options the year before that. I should start a pool on what it will be called next year.

It's really just science for freshman who have no academic aspirations, science for the "low levels." ("Just science" is the best kind.)

Two years ago I had two brilliant students in the inclusion class. Their minds moved far faster than mine, and faster than can be tolerated in a public school setting. If either survives high school, they will do fine, and I suspect they will do fine even if neither graduates.

Atoms are mostly space. We say this, but it's mostly words to students, words they will memorize long enough to fill in a bubble with a Number 2 pencil, then forget. This kind of ability will get you far today, as long as no wisdom is required (and it rarely is).

The classic textbook diagram misrepresents the space--the book would have to be the size of a football field to do the atom justice. It's also a generation or two removed from the electron cloud model (never mind quantum field theory). I learned to be careful when discussing pictures of models--some children get upset when they learn that the book "tells lies."

Science is stories framed within empiricism.

I took the class into the hallway to get a sense of how much space is in an atom. I used a wheat berry as the nucleus. Several students volunteered to carry electrons. Each was given a grain of sand from a beach in Cape May, sent to me by my cousin when sister died. I told the class this.

My electrons were buzzing around the hallway--every now and again I needed to remind a sleepy student to keep moving. We needed about 150 feet, but the hallway was too short. Still, 100 feet between a wheat berry and a grain of sand leaves a lot of space.

The brightest child in class grasped his head and asked me to stop. "This can't be science!" It was too much for him.

This is why I teach.


Linda Fox said...

Great idea - I'm going to steal it (when you borrow, you don't change anything. I steal - I make changes).

I'll be teaching Physical Science & Chemistry this fall, so this is perfect for both.

doyle said...

I likely stole it from someone else--teachers make great thieves.

I look forward to comparing notes!