Following their mentor’s precise yet gentle instructions, two students make a batch of glass spheres the size of Ping-Pong balls, help her fuse a dozen of them onto an orb of glowing glass using a propane torch, then carefully place the knobby molten globe into an annealing oven to cool.

Now Robin Cass gives them their next assignment – make a bunch of “feelers” – and a silent demonstration. She sits at a bench twirling a long pipe topped by a blob of honeylike glass that she pinches and pulls with tongs into three buds. Then she stands and swings the pipe, allowing centrifugal force to stretch the blob into a sinuous stalk sprouting three antennae.

‘‘You’re coaxing it into shape rather than pummeling it,’’ she says, as the students, Sarah Vaughn, 29, and Celia Garland, 21, set out to re-enact her moves.

The glass balls and feelers created on this morning in the hot shop of Rochester Institute of Technology’s School for American Crafts may end up in works displayed in galleries and museums worldwide. Resembling creatures or plants from another planet, Cass’ sculptures offer a compelling mix of sci-fi weirdness and fine craftsmanship.

And the students who helped Cass create the elements in those sculptures may end up creating their own museum-worthy artworks one day.

Cass, 44, has long been committed to creating both art and artists. She does so by wielding her roles as an innovative artist and educator in the same dexterous way she makes sculpture: choreographing, delegating, composing, and taking risks.

In the 16 years since she began teaching at RIT, Cass has risen from adjunct instructor to co-chair of the glass department to chair of the School for American Crafts to – as of January – associate dean of the College of Imaging Arts and Sciences.

Calling this latest role “a grand experiment,’’ she acknowledges that it will demand much of her time and energy. “But I am determined to maintain my active studio practice,’’ she says.

That makes her hot-shop collaborations all the more essential. “I think in terms of cooking,” says Cass, whose glassmaking tools include such junk-store finds as a cast-iron griddle with egg-shaped indentations – “perfect for making eyeballs.’’ Comparing her assistants to sous-chefs, Cass says, “They chop the onions. I decide how much to put in the soup.’’

Those decisions are made miles away, in the solitude of her home studio.

Riding the line
Large, leaflike ears of waxy glass are heaped on metal shelves. Other shelves bristle with piles of glass antennae and antlers and long, ridged horns. Orbs, glowing from within like cats’ eyes, seem to peer from every surface.

“I’m the queen of parts!” Cass crows, sweeping her arms around the second-floor bedroom, one of two that serve as studio space in the Rochester house she shares with her husband, graphic designer Bill Klingensmith.

Here, she says, without the urgency and coordination required in the hot shop, “I can make decisions at a leisurely pace.”

Those deliberations are driven by her desire, as she often puts it, “to ride the line”  between the grotesque and the beautiful, attraction and repulsion, between animal and vegetable, animate and inanimate, natural and artificial.

Another crucial line Cass treads is the one between science and art. Growing up in the Boston area in a science-oriented family (her mother is a psychiatrist, her father a general practitioner), Cass was fascinated by the dioramas in the Peabody Museum – “by this idea of contained worlds, separate worlds … having the natural world curated and archived.”

Another deep and lasting influence, she says, was going with her father to see “really fantastical, cheesy sci-fi movies. I saw Aliens way too young.”

But finding the means and the medium to create her own imaginary worlds was a struggle. After dabbling in anthropology and political science at McGill University in Montreal, she became a sculpture major at Rhode Island School of Design in 1990.

There, yearning for “a foundation, some material to start with,” she took an elective in glass. She soon realized “this is something I could stay interested in, that could be an anchor for a long time.”

“The material seduces you, the way you can use it to pull in light, the range of qualities it can express,” she says. “It can be a cold chunk or a hot fluid.” It also requires discipline to work with, she learned, “but you didn’t have to be all in your hands or all in your head.”

And though the field of glass had long been dominated by men, she found inspiring female teachers at RISD. “It’s important to have role models who make you feel comfortable in a field once considered macho.’’

In addition, glass has a rich history as a material used in scientific research, she says. “From alchemical vessels to lenses, glass has had a profound effect on how we observe and understand the natural world.

“It’s a workhorse of a material, but also poetic. It’s got that whole range.”

Anything goes
After graduating with a BFA and working in production glass studios in Alaska and New England to hone her skills, Cass entered the MFA program at Alfred University. Two years later, in 1998, she graduated and began teaching at RIT.

Now she teaches not only in Rochester, but also in workshops around the world.

Hiroshi Yamano, one of Japan’s foremost glass artists, invited Cass to teach at Osaka University of Arts, where he chairs the glass program, because of her ability to impart her innovative techniques to students –  and to inspire them to use those skills “to create their own worlds and own unique story.”

Cass also shows, by example, how to master traditional skills without being confined by them. For example, flowers have long been used in glass, she says, “but it’s interesting to me to subvert that decorative element and instill it with a bit of sentience – as if it’s watching you.’’

She also defies traditional technical dogma, which bans adhesives and dictates that “everything needs to be permanent enough to go through a dishwasher.’’

After gluing separate elements into a single form, she sandblasts it, then treats it “like a canvas” – spraying, wiping, and brushing it with oil paint. “For me,” she says, “anything goes.”

That includes experimenting with new technology. She and RIT ceramics professor Jane Shellenbarger will be leading a pilot project to use 3D printers and scanning equipment in the glass and ceramics curriculum.

This investigative approach to art is equivalent to that of the “pure research” of more traditional academic fields, she argues – an idea she plans to push in her new role at the tech-oriented RIT.

The value of studio art, like that of scientific research for its own sake, may not be immediately apparent, she says. “But that’s where the new ideas come from, the cutting-edge stuff.”

Sebby Wilson Jacobson is a freelance writer, editor, and teacher in Rochester, New York.