In my very first Experimental Error column in 2010, I made fun of standard science demonstrations, especially one I called “Let’s All Gawk at Liquid Nitrogen.” Why, I complained, were certain experiments so universal, especially when they showed nothing about what scientists actually do?
Now, 7 years and 82 columns later, I’m a dad. A dad who works in cryobiology. A dad whose daughter’s kindergarten teacher found out I’m a scientist. You know where this is going.
“You have to come do a science experiment in our class!” the teacher enthused.
“Uh … any subject in particular?”
“Nope! Just anything fun!”
I spent the next week trying to think of a science demonstration that would delight and educate while showing the kindergartners that (a) scientists ask real questions; (b) a career in science is exciting, rewarding, and realistic; and (c) Maya’s dad is not lame.
Oh, screw it. I’m doing liquid nitrogen.
In my defense, I objected to this kind of demonstration before I became intimately familiar with the attention spans of young children. Maybe I naïvely pictured a room full of dutiful cherubs, listening raptly while I expounded on the intricacies of protein tertiary structure. I now know that a 6-year-old can ask you sincerely how the universe was formed—and then, while you’re half a sentence into your answer, run away laughing with her brother’s shorts on her head.
So, the night before my semi-involuntary demo, I select the most interesting things to dip in liquid nitrogen. A latex glove is always good, because it’s easy to see it transition from stretchy to brittle. There’s the classic balloon, which shrinks when chilled because the bouncing molecules inside slow down, and then it reinflates itself as it warms. And, finally, it wouldn’t be a liquid nitrogen show without shattering a bouquet of flowers into tiny pieces.
At the supermarket, the cashier gives me an “Ooh, who’s the special lady?” look when she sees my purchases. What kind of romantic evening does she think I’m planning that involves a bouquet of roses, a latex glove, and a balloon?
The next morning, I drive Maya and a dewar of liquid nitrogen to school. I wheel the dewar, a gray metal cylinder that probably looks a bit bomb-like, past the security guard.
“It’s for science,” I tell him—which I later realize explains nothing, but works anyway. Hashtag lab coat privilege.
Once in the classroom, I unroll a line of painter’s tape onto the floor and Maya’s teacher promises (inaccurately, I would soon learn) that all the kindergartners will stay behind the line during the demonstration.
Honestly, I didn’t know how the kids would react. I worried that one slip-up on my part—one uncool multisyllabic science term, one admission that I don’t know what a fidget spinner is—would permanently label me in their eyes as one more boring and out-of-touch adult.
I underestimated the power of liquid nitrogen.
As soon as I pour that chilly science juice into a bucket, a foot-high tidal wave of nitrogen gas rushes toward the students. That happens all the time at work, and I usually ignore it. If anything, it’s kind of annoying, because I can’t see what I’m working with as easily.
But these kids have never seen anything like it. A gas, a visible gas, rolling toward them like a cloud. “Are you kidding me?” I can hear them thinking. “Maya’s dad just POURED A CLOUD. You know who else does that? Freaking deities, that’s who.”
From that moment, I can do no wrong. They love the glove, marvel at the balloon, and laugh at the pulverized rose. The teacher has to order them back behind the painter’s tape a few times because they’re just so interested in getting close to the nitrogen that they can’t stop themselves from creeping forward. And to think that I was worried I’d arrive in a classroom of jaded kids who’d roll their eyes and count the minutes until recess.
I was never that jaded kid, but I felt like most of my classmates were. I remember when I volunteered my dad to chaperone our seventh-grade field trip to the National Gallery of Art. He’s a did-you-know kind of dad who once made the callbacks for Jeopardy! As he led our group of adolescents through the National Mall, he shared facts about the various monuments and museums we passed. My classmates could not have cared less. “Wow, Dad knows a lot,” I remember thinking. “How embarrassing.”
But most kindergartners haven’t yet discovered cynicism. Impatience, yes, and a relentless pursuit of sugar, and an inordinate fascination with synonyms for “posterior,” but the need to appear cooler-than-thou is simply not their instinct. No one seems to fear humiliation over expressing their legitimate enjoyment of science.
“What happens if you drink it?” one girl asks. I anticipated that question, and I tell her about storyteller Mike Daisey’s “Great Men of Genius” monologue about Nikola Tesla, in which he describes a high school classmate who attempted that very experiment and couldn’t speak for a month. This answer stuns them, not because of the fear of esophageal injury, but because they can’t imagine not speaking for a month.
“What happens if you drink it?” is a typical kindergarten question, and the answer can usually be boiled down to some variation of “Bad things, so don’t.” But in retrospect, it’s actually a great insight into the scientific mind with which we all start life. What happens if?
Yet somehow, between “What happens if?” and college, we lose a lot of potential scientists. Is it because they stop wondering “What happens if”? Or is it because we drown them in Latin? Or because we give them all the answers, rather than encouraging them to ask questions and find the answers on their own?
I still remember a great example of encouraging genuine investigation in my ninth-grade Introductory Physical Science class. We were told, at the beginning of the year, that someday we’d be handed a bottle of sludge and, using what we’d learned, we’d have to figure out what it was made of. Impossible, we thought. A science project without instructions? Just some knowledge, some lab equipment, and a bottle of soupy green or black stuff? Yet, thanks to the techniques Ms. Newsom taught us, we could separate the various compounds in the sludge. It felt like unraveling a mystery.
The demo ends, and the kindergartners run out to recess, where they’ll ask “What happens if?” about the sandbox, the trees, their friends. That’s geology, botany, and psychology.
The point isn’t that everyone should become a scientist. Frankly, there aren’t enough jobs to make that happen. (Besides, we also need people to do other important jobs, like voting to deny scientists funding.) But how great would it be if everyone retained a sense of wonder, an openness to learning, into adulthood?
Impressing young kids with science, it turns out, is easy. The subject is so darn awesome that it sells itself.
“That was so cool!” the teacher says as I apologetically pick flower bits out of her carpet. “You have to come back next year!”
Yeah. I think I do.