As she speaks, her eighth-grade students spout through snorkels and gesture silently in an awkward effort to construct a "space station" in the "microgravity" of the camp's pool.
Next door in the gym, Donna Lucas, a teacher at Glendale's Zion Lutheran school, makes the same point as one of her fifth-grade students whirls upside-down in a red, white and blue gyroscopic "space ball."
"Often kids go through the whole week and don't even know it's science they've been studying," says Astrocamp instructor Sara Swedlund, 25. "They think they've been playing all week."
Like Keller, Swedlund says she sees the camp as a place to apply education theory, a lab in which to work on applying fervid counterforce to some students' ingrained resistance to science.
"I want to get them excited," she says.
So Swedlund grins as one student puts her hand on a beach ball-sized Vandegraph generator in the electricity and magnetism lab and sees her hair shoot out straight in a static-charged halo. And she laughs along with the students when they all link hands and then recoil as a shock rips through their arms.
Their muscles are controlled by electrical impulses, Swedlund explains.
"This room is overflowing with excited electrons," she says.
On the last day, when the sky turns blue, Swedlund is beside the students as they look at the sun through barrel-sized computer-directed telescopes. Those squiggles--prominences--leaping from the sun's surface are examples of the strength of the sun's magnetic field.
Sometimes the science link is obvious, as when students design their own Mars landers and drop them onto a rocky surface, or when they launch rockets made from plastic bottles and use trigonometry to calculate the altitude attained (200 feet is a common height).
In one class, Keller lectures on lights and lasers, letting the kids experiment in a dark room that fills with artificial fog and the music of R.E.M.
At one point, the students look through diffraction glasses as lights containing different gases--hydrogen, helium, nitrogen, neon--break up into rainbows.
"What makes light?" Keller asks.
"Jiggling electrons!" a student answers.
And different colors, Keller says, represent different temperatures and compositions--which is how astronomers determine what stars are made of.
"Astronomy," he concludes, "is all about light."
That night his students hike silently through the forest, their wet high-tops crunching in the snow. When the clouds briefly part, an earlier lesson resurfaces.
"Look," a student whispers, pointing to a glaring new light source. "Orion!" There are, however, parts of the Astrocamp curriculum that never quite loop back to astronomy.
At first, Goodsell says, the camp tried to integrate its "ropes course" by saying it simulated astronaut training. Now, the instructors admit that the only connection to science is to psychology.
"Students are often afraid of physical challenges, and often they're afraid of the sciences," Goodsell says. "If they do things that give them higher self-esteem, maybe they'll feel they can accomplish more in life."
So it is that squeals and chants often infiltrate the serious science talk, as students in rock-climbing harnesses clamber about on poles and cables suspended up near the tree line.
The task that stirs the greatest buzz among campers is the "power pole."
With snow still blowing and temperatures dipping fast, Keller's 12 charges approach a towering post stuck into a meadow.
The routine has been standardized.
"My name is Thanh, and I accept this challenge. Do you support me?" an eighth-grader asks. As his classmates cheer, he climbs skyward.
At the top of the 30-foot pole, each student struggles to take the last step and stand upright on the pinnacle. A few back down. One girl in another group reaches the top and then sits there sobbing in terror.
Most, however, wobble to their feet. Then, at their instructor's urging, they leap into the air, grasping for a trapeze that dangles a few feet from their fingers.
When all the students have been lowered to the ground, Keller gathers them and asks for "one word to describe what you're feeling now."
"Cold!" several shriek, huffing steam and patting their mittens together.
Keller grimaces and adjusts the assignment: "OK, any word that isn't thermal?"
Brittany, a seventh-grader, looks up beaming. "It's a thermal word," she says, "but . . . ."
"Go ahead," Keller says. "How'd it make you feel?"
"Cool!" she yelps.