A few of my goldfish made the annual pilgrimage from my backyard puddles to classroom aquariums.

The classrooms were empty as I cajoled bubblers and filters to return to life. Saturday classrooms feel like midnight cemeteries.

Each classroom has a list of essential questions defining the ultimate goals of a unit. Our district spend gobs of money getting Grant Wiggins to talk to us, and by golly, we're going to keep posting the questions.

I have no problem with essential questions. I have no problem with Genesis, either. If we're serious about either, you might want to think twice before using them in a public school.

Grant Wiggins, the father of Understanding by Design, says that essential questions are "broad in scope and timeless by nature. They are perpetually arguable."

Indeed. I have only, alas, 48 minutes in a period.

My fish will intrigue a few students. My essential questions, which I love to develop, will not. I work with 15 year old man childs. Woman childs. Children lost in the magical thinking of brains seduced by sex hormones literally resetting their genomic activity, sex hormones that slide right past the phospholipid bilayers of their cell membranes, causing pieces of quiescent DNA to be transcribed, to wake up, to make proteins that will lead to bad decisions and dangerous behaviors that will usually result in another generation of human DNA.

Desire.

***

I watched my cockroach probe the edge of the Petri dish with its antennae, searching for a gap large enough to escape the scrutiny of young adult humans peering through the stereoscope. The same cockroach now sits in a bucket on my stoop on a wet, snowy night, waiting for me to figure out where to release it.

In science, we learn to avoid words like "want" and "desire," because we cannot assume that a, say, proton "wants" to be closer to an electron, though we can empirically see some sort of attraction. Everything made of stuff is attracted to everything else made of stuff--we call it gravity, and maybe it no longer amazes most folks, but it still amazes the poop out of me.

So when Doreen sees the cockroach clean its antenna by dragging it through its palps, I am supposed to correct her by explaining that cockroaches do not "want," they just "do."

I keep silent. This particular cockroach on this particular day clearly wanted to clean its antenna. I wasn't going to argue the point with a 15 year old H. sapiens, not when it took me two months to get her to trust her eyes over the words in a textbook.

***

And what is desire? What is attraction?

It is (perhaps) a uniquely human thing to imagine a better life, and work towards a long range goal. Immediate behaviors to attain long-term goals require either a fine imagination or the jackboot up the gluteus of instinct.

I remember very little about 15, but I remember this much--I wanted Desiree, desired her, was attracted to her, use whatever verb you care to use, beyond reason or imagination or sense.

I was like an electron trapped by a proton, and about as conscious.

If desire is reduced to seeking behaviors that reduce the ache of desire, then my cockroach is capable of desire. No surprise there, tautologous as it is. No, the surprise is recognizing that what I felt when I was 15, something I may have called "love" or "lust" or "friendship" was no more (or less) real than the need for the cockroach to escape its Petri prison.

Accepting that a cockroach may have desires is not elevating it to the hallowed plane of a Harvard professor searching her cerebral cortex for the phrase that will impress her suitor with her cleverness, her literateness, her, um, humanness.

And I do not mean to belittle the professor. But aren't there days when even the elite among us would like our desires to be as simple as the cockroach's.

(And here's the dirty little secret--on most days, they are.)

***

And what do we know of cockroach desire before the testosterone and estrogen warp us beyond our human nature?

We know thirst.

One of the biggest mistakes I made as a resident was letting a mother be a mother. Her baby was severely dehydrated, his salt concentrations dangerously imbalanced. Correcting the imbalances too quickly could lead to his death.

His mother let him drink. And drink. The baby boy sucked on the Pedialyte with all the urgency and need of Athena emerging from Zeus' head, the need electrons feel for protons, the need I felt for Desiree.

The baby seized. The baby, now in his twenties, may not be the same person he would have been had I thwarted his desires. I do not know how much brain damage was done.

Incomprehensible want, behaviors altered for unimagined (and unimaginable) ends, for no reason beyond the attraction of desire.

So when Doreen tells me the cockroach wants to clean itself, I do not correct her, because she is right.

***

My essential questions in class keep drifting back to matter and energy, and because I do not pretend to have a grasp of either, drift even further back to "why?"

I see essential questions like some see democracy--if either truly worked, they would be banned. Public schools cannot tolerate children seeking answers to essential questions. We expect them to sit (for 48 minutes, no more, no less) at a desk studying a subject they did not choose.

If I want to teach science, I need to go outside, and I need to be less vocal.

That I continue to teach inside, modulating my voice like an orator (or a clown), hoping to maintain their attention long enough to skewer them with the NJ Core Curriculum Standard 5.12.1.A3 or 5.12.4.B4, shows I am human, able to thwart real desires with imagined riches given to those who persevere.

And I am failing. I am a good teacher, but not a great one.

If I were a great one, a child (or two or three) would stand up on a beautiful day, and walk out into the sun and set herself by a pond or a tree and simply observe.

And if I were truly a science teacher, I would follow the children out the door.