Saturday, July 12, 2014

NGSS and food: starving for accuracy

“Science is the belief in the ignorance of experts."
Richard Feynman



I am trying to get a handle on my seemingly irrational visceral response to the Next Generation Science Standards. I should be lovin' this up, especially since philosophically the folks at NGSS and I are on the same page. The Visigoths of Ignorance are banging on national psyche, and we are teetering on the brink of Age of Magick.


I am a bloody mix of superstitions, awe, and and mortality with an inkling of the power of science, and as such may put too much trust in my enteric nervous system ("gut feelings"), but eventually I wrestle with my viscera enough to either make sense of these feelings, or abandon them.

So what's the problem? Ah, the devil (there's that magick again) is again in the details.
***

If you want to learn science, you're going to have to let go of some things you believed to be true. Not all things, not even all things irrational, how dull would that be?

But some things, some things that you believe in your core to be true. The ground is mostly solid stuff. The sun rises and sets. You are, in some sense, immortal.

From Johannes Stabius’s Pronosticon (1503) via Philadelphia Are Center for History of Science

If we're going to teach young students science, and if we're going to insist on some set of national standards (though why we need "standards" in a field whose strength is blasting holes through standards through the ages), we need to get the basic stuff right.

Not mostly right, or almost right, or, please-forgive-us-we're-a-committee right
We need to get what we do know (or at least think we know) dead on balls accurate.

And the NGSS whiffed....

Energy can be “produced,” “used,” or “released” by converting stored energy. Plants capture energy from sunlight, which can later be used as fuel or food.
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One of my pet peeves is our inability to grasp what food is--we screw up the concept at so many levels. For now, I'll limit this to its definition.

Food is stuff, not free energy. It is very unstable stuff, and when it breaks down, lots of energy is released, but we end up with the same amount of stuff we started with, just in different forms.

Plants put stable stuff together to make food. This takes energy, energy plants glom from sunlight. If I want to build an (unstable) house of cards, I take a deck of 54 cards, use energy to arrange them a certain way, but when I am finished, I still have exactly the stuff I started with, 54 cards.

Food is represented by the house of cards, not the energy I used to build the house. Plants do not convert sunlight into food, no more than I create cards out of thin air when building the flimsy house.

If the soul of biology is the theory of evolutions, its heart is the babble of bubbling life trying to make or grab food, breaking it down to release free energy and to rearrange its parts to build new things.

I preach from Day One: Follow the "stuff," follow the free energy, the two are entwined but separate.
***

"Plants capture energy from sunlight, which can later be used as fuel or food." So what's the big deal?

Energy is not food. Plants are not made of sunlight.  It seems so, though, given how big trees can get, seemingly from little more than air and water.




We are surrounded by trees, huge organisms weighing tons and tons While we bemoan folks for not being able to see the forest for the trees, many of my lambs miss the trees as well.

The NGSS gets this wrong--free energy is used to make food, true, but energy is not used as food. And now we've given thousands of elementary teachers permission to keep getting this wrong.

2 comments:

Tom Hathorn said...

This post critiques one statement in Appendix E of the NGSS (a grade 3-5 progression statement: Energy can be “produced,” “used,” or “released” by converting stored energy. Plants capture energy from sunlight, which can later be used as fuel or food.).

I'd like to look for more evidence in the NGSS grade 3-5 standards, and I'd like to invite a reexamination of the claims in this post related to the words "food" and "energy," and especially the claim made about whether NGSS has "given thousands of elementary teachers permission to keep getting this wrong."

The way that educators use standards is pretty important. NGSS is calling for us to integrate three dimensions, and build coherence within and across grade levels. We are cautioned against viewing standards as checklists, and/or treating the three dimensions as separate pieces. I'd like to RE-contextualize the statement in Appendix E,looking at several related parts of the NGSS to more carefully understand that one statement.

When I consider (1) the whole set of statements in the PS3.D progression, and (2) the numerous details of the grade 3-5 standards (Performance Expectations and their supporting Disciplinary Core Ideas), I do NOT come to the same conclusion that NGSS is perpetuating misconceptions that arise from a conflict between the everyday and scientific uses of the words, "food" and "energy." Consider this greater body of evidence, and see what you think...

Progressions (Appendix E)
Here's the complete NGSS progression, PS3.D - Energy in chemical processes and everyday life:
K-2: Sunlight warms Earth’s surface.
3-5: Energy can be “produced,” “used,” or “released” by converting stored energy. Plants capture energy from sunlight, which can later be used as fuel or food.
6-8: Sunlight is captured by plants and used in a reaction to produce sugar molecules, which can be reversed by burning those molecules to release energy.
9-12: Photosynthesis is the primary biological means of capturing radiation from the sun; energy cannot be destroyed, it can be converted to less useful forms.

Grades 3-5 NGSS Standards
Here are the details found in the specific Standards, Performance Expectations, and Disciplinary Core Ideas (grades 4 and 5):

Grade 4, from the Standard 4-PS3 Energy:
DCIs that support the Standard:
PS3.B: Conservation of Energy and EnergyTransfer
Light also transfers energy from place to place. (4-PS3-2)

PS3.D: Energy in Chemical Processes and Everyday Life
The expression “produce energy” typically refers to the conversion of stored energy into a desired form for practical use. (4-PS3-4)

Grade 5, from the Standard 5-PS3 Energy:
Performance Expectation 5-PS3-1: Use models to describe that that energy in animals’ food (used for body repair, growth, motion, and to maintain body warmth) was once energy from the sun.
[Clarification Statement: Examples of models could include diagrams, and flow charts.]

...and the DCIs that support the Standard 5-PS3 Energy:
PS3.D: Energy in Chemical Processes and Everyday Life
The energy released [from] food was once energy from the sun that was captured by plants in the chemical process that forms plant matter (from air and water). (5-PS3-1)

LS1.C: Organization for Matter and Energy Flow in Organisms
Food provides animals with the materials they need for body repair and growth and the energy they need to maintain body warmth and for motion. (secondary to 5-PS3-1)

doyle said...

Dear Tom,

Swamped as I am with SGOs, UbDs, and other acronyms that nip at my heels by day (and in dreams by night), I do not have the luxury to spend the time you deserve on a more nuanced response, so here's the brief version:

I love the thrust of the NGSS, and yes, I critiqued a single statement. The language perpetuates the myth that sunlight is converted into food.

Yes, a teacher with a solid background in science will not get this wrong. Too many of our teachers (at all levels) have misguided understandings on how the natural world works.

It's a simple enough thing to fix the language. That way this cranky science teacher can spend more time pondering the mysteries of New Jersey SGOs and NSTA folks can spend more time teaching elementary teachers where food comes from.