Sunday, November 23, 2008

Stuck on bonding

I need help.

I love chemistry, both because our models work so well to explain how substances react, and because chemistry problems feel like fun puzzles.

I can show kids how to figure out the valence electrons using the periodic table, and many of them will see why some elements tend to form ionic bonds while others will form covalent bonds.

Still, I feel like I'm teaching Clever Hans the Math Horse how to count--I might be able to get Hans to pound the ground a few times with his hoof, but no way is he comprehending why.

A few of my freshmen will paw at the ground to make others happy (and some have been conditioned to enjoy being correct without knowing why), but that's not science.
Oh, well, we're preparing them for the real world, industry, where they'll be expected to manipulate data. Aherm, discipline, aherm, aherm. They need to know how to produce, yes, or else they'll be flipping burgers, yes, aherm, aherm.

Clever Hans, it turns out, was not so clever, but at least he got his daily oats.

Anybody have ideas how to put the cart before the horse and truly teach chemistry to freshmen taking physical science before they can shave?

I don't need dog-and-pony ideas. I can blow things up, make them fizz, change colors, and stink up the whole science wing. I can be the Razzmatazz Master, make kids say "wow!", and create the Rockwellesque scene perfect for the bulletin board on Back to School Night.

How can I get a 14 year old to grasp orbitals and particles and waves in a way more challenging than the Paw-the-Ground-and-Neigh-When-I Smile method?

(I'm not sure I can. Not sure anyone can. And if we cannot, how much harm are we doing pretending that we can?)


Photo of Clever Hans from Animal Intelligence.

9 comments:

Louise Maine said...

I used to take classes into the gym to be the electrons and spin in pairs (oppositely of course). They would orbit too (well, one year as it was fun but dangerous). This only worked if I had a large enough class or a bunch of atoms with small atomic numbers. They still had a hard time with the bonding thing but a better idea of some of the relationships. I am trying to remember (haven't taught it in awhile).

doyle said...

Ah, a good idea for our CP kids, and my Integrated Science kids would enjoy this, but not sure it helps them get the energy levels.

I used them as electrons, told them only 2 could sit in the "sleepy" chair, only 8 could sit in the next less relaxed chairs, etc., but while I can get them to learn the numbers, and while some get that each level represents a certain energy level, most do not understand what any of this means.

I may chat about the chemistry of cooking on Wednesday--it's a half day, the turkeys are getting stuffed, and I bet it will interest them more than valence electrons.

Thanks for your help!

lucychili said...

What was it that made those concepts crystal clear for you?

Blogger In Middle-earth said...

Kia ora Michael

Fourteen year olds? Atomic orbitals? Aherm.

I have always been a firm believer in the developments that happen in the brain. Concepts, especially spatial ones, are definitely ones that require a certain base development in kids before they can grasp the idea.

I have always wondered at the wisdom (and worth) of teaching about electron orbitals to young learners, especially if there is a real chance that they will not have the conceptual development to be able to understand what it's all about.

Now bonding is different - the old stick model (I know, I know - chemists don't like this much) is something that kids can identify with. Valency, or co-called combining power, is really as much as some fourteen year olds can cope with in Chemistry.

Forget about the Periodic Table at that age. It's not needed anyway.

Last month I wrote a post about pedagogy and scaffolding. It is still the most popular post on my blog. I used, as an example, the steps that lead up to writing a balanced chemical equation.

All of the steps that a learner required to grasp are achievable by a fourteen year old. They are:

* understanding of the particle theory of matter
* awareness that the smallest discrete particle of matter is the atom
* knowledge that elements are made up of atoms that are all the same
* knowledge that chemical symbols can describe atoms of elements
* appreciation of the way in which most atoms join with each other
* knowledge of numeracy used in writing correct chemical formulae
* awareness that atom combinations follow predictable patterns
* knowledge of numeracy used in writing chemical equations
* appreciation of the conservation principle of matter

Most of the ideas are easy to find practical activities for kids to do to find out things for themselves.

Tell me, is it part of your curriculum to teach electron pairs and electron orbitals to fourteen year olds? If it is, I'd say that your curriculum leaders need to rethink the levels that these concepts are introduced to.

Ka kite
from Middle-earth

doyle said...

G'morning lucychili,

Once the world's solidity dissolved for me (a combination of brain maturity and the usual mid-adolescence questioning, our family pulling out of the Church, and my most severe concussion), I became open to models as models, the meta behind the physical world, but not metaphysical in the current philosophical sense.

Not sure I could have gotten it as a 9th grader, and certainly would not have cared if I could.

Kia-ora Ken,

I tossed about last night after tossing metaphysics out the window, and realized a less narrow view of the word works just fine.

I agree, and I am going to stick to ball and stick models this week (though I need to go scrub my plans).

I am going to go lift your ideas, and the kids will be be thankful.

No, blame me, not the curriculum--I do not know how to pretend that kids know much about bonding if we do not involve at least a simple version of energy levels. The curriculum is vague enough that I can simplify things a bit.

Chemistry/physics loses a bit of its luster when shadows of concepts are taught, but you're right. I am asking too much.

Just wondering if it's woth covering if we just cover the shadows.

(re: the Periodic Table--we're expected to cover it, and I had a good discussion with a teacher I admire who believes the discipline of reading the table is a transferable skill. I'd rather use bus schedules to teach how to read tables, but that's where the narrowness of teaching in specialized fields hurts the kids. Of course, I could teach the bus schedule and pretend it's to prepare the kids for the Periodic Table; at least the kids learn something useful that way.)

I am going to spend some time over at your blog this afternoon. Thanks for your help!

Blogger In Middle-earth said...

Kia ora Michael

I know where you are coming from when you say "I could teach the bus schedule and pretend it's to prepare the kids for the Periodic Table".

I agree with your admired friend. A transferable skill is a transferable skill. Why not teach them how to read the Periodic Table?

If you truly believe that it is a transferable skill (and I do) then surely you're teaching them something that will be useful to them, ultimately, and not necessarily just with their Chemistry.

If you are covering a prescription requirement at the same time, feel good about it.

Hey, it's okay for the teacher to enjoy some things too y'know.

Check this out. It's on elements compounds and mixtures. If you find it useful, I have many others - not all to the same design and format as this. Variety helps.

Ka kite

doyle said...

Kia Ora Ken

Great link!

And thanks for the encouragement. I had a good discussion about presenting the Periodic Table and valence electrons with another teacher here. He suggested viewing the PT as a neighborhood of the "haves" and "have-nots"--gets into all kinds of interesting metaphors, and the kids like comparisons to our neighborhood.

I don't disagree about transferable skills--just wondering in which class do the kids actually get to learn how to read train schedules. Might be easier to transfer routine/authentic table reading to more esoteric ones.

We have a break coming up in 2 days--I'm going to be nosing around a couple of sites in your part of the world.

Again, thanks!

lucychili said...

It is amazing how quite complex ideas can be modelled with simple symbols.
This is electrical and magnetic fields on a dipole antenna. http://wwwhome.cs.utwente.nl/~ptdeboer/ham/xnecview/dipole_anim.html

I am usually looking for things which make good poetry or painting fodder but it is interesting shifting gear. =)

doyle said...

Dear Lucychili,

Symbols are amazing--the simple string of symbols banged here by our keyboards across a planet would stun me into inactivity if I dwelled on it too much.

What's even more amazing is how few of us are taking advantage of what's available, sometimes even within my own building.

I work with amazing people in Bloomfield--I need to remember to just ask for help.