Education trends come and go: Mandatory pledges of allegiance, the new math, forcing left-handed children to write with the right hand.
And then there is the classroom chair. In New York City public schools, a top chair of choice since the mid-1990s has been the Model 114, also known as the "super stacker," 15 pounds of steel, sawdust and resin that comes in 22 colors and has a basic, unyielding design little changed from its wooden forebears.
"They don't die," said Ali Salehi, the senior vice president for engineering and operations for Columbia Manufacturing, a 135-year-old company in Westfield, Mass., that makes the super stacker. "They just don't die."
The staying power of the super stacker, a version of which can be found in schools all over the United States, is a symbol of continuity in a world of constant change. Children who attend the same schools their parents attended are likely to, at some point, plunk down in the very same kinds of seats, if not the very same seats.
But in some quarters, the chair and others like it are seen as stubborn holdovers from before the age of ergonomics, when American schools' main job was to turn out upright citizens, and rote learning was the student's lot.
"The chair, in short, originated in the industrial ordering of education," said David W. Orr, an environmental studies professor at Oberlin College who frequently writes about design. "It is maintained by profit-seeking school suppliers and unimaginative administrators who see no other possible arrangement of the body, or bodies, or any possible downside to the lower back from six hours of enforced sitting."
Wes Bradley, the principal of Thomas Nelson High School in Bardstown, Ky., said he doubted many school districts had "ever had a discussion about chairs."
Never in the six years he taught in a Bronx high school, Mr. Bradley said, had he seen chairs like the 1,000 new ones he put into his school's 40 classrooms in August -- each chair a vessel of student sovereignty.
Pupils can turn them to face front or back, or use a handle to pull them into football-like huddles or to fan out for more independent work. While not perfect, Mr. Bradley said, they are "human friendly, form to the body" and come in "energizing colors."
In Albuquerque, as Michael P. Stanton set out to furnish the nex+Gen Academy High School that was opening in 2010, he sought seats to match its progressive philosophy, which relies on common areas and "learning studios" with no doors, instead of classrooms.
The new chairs, Dr. Stanton, the principal, said, "are popular." They come in two styles, both with wheels. One model has holes like a Wiffle ball. The other is fully cushioned.
"I chose them due to their flexibility, in the seat itself, so the students could 'wiggle' or move easily without leaving their seat," Melissa A. Grant, the Albuquerque Public Schools' interior designer, said in an e-mail.
Anecdotally, administrators who have used newer, more flexible or free-moving chairs say that children find their new seats more comfortable and that they seem more engaged. Few studies have been conducted on whether chairs affect student performance, though a four-year study of 400 students conducted by a German nonprofit devoted to "posture and mobilization support" said children were able to concentrate for longer periods if they were given more mobile seats, combined with lesson plans that involved moving around.
But unleashing students is a disputable concept, particularly in complicated learning environments. After all, schools have traditionally been synonymous with a hushed subservience reflected in the Industrial Age's glib commands: "Do not slouch"; "Respect your elders"; "Speak when spoken to" -- notions that some educators still find worthwhile today.
"They did not have solid plastic a hundred years ago, but the concept is the same," Bob Keller, the chairman of Nickerson Corporation, said of the Columbia chairs. Nickerson is the main distributor of chairs for the New York City public schools, including Columbia's super stacker. "They are not made for comfort. They are made for students to sit up and for students to be working. They are what we call a straight-backed chair."
As with most issues the city confronts, cost is paramount.
The chairs at Thomas Nelson High School, made by Hon, cost roughly $120 apiece, though Mr. Bradley said the school got discounts of 50 percent to 60 percent based on state contracts; and the Albuquerque chairs, manufactured by Izzy, cost $115 per chair on an order of 400. The super stacker model costs New York's Education Department $45 to $70, depending on the size of the order, Mr. Keller said.
The schools chancellor, Dennis M. Walcott, said the city embraced innovation, and he emphasized that it was "always open" to cost-efficient opportunities to buy chairs fitting students' needs.
"If there is an ability to balance those two, we are always interested in seeing what is out there," he said, noting that many of these kinds of decisions were handled at individual schools.
But the chair the city has gone to time and again, Mr. Keller said, is the super stacker, which Columbia's Web site says was designed "to optimize student comfort and maximize stackability."
Its legs, forged into shiny tubes, consist of low-carbon steel imported from two factories: one in southern Canada and the other in Massachusetts. Steel gliders and support rods are robotically welded to the frame. The seat and back are separate pieces, each made of sawdust and resins that are compression-molded under high temperatures and usually coated with a trademarked paint called "speck fleck," Mr. Salehi of Columbia said.
Tamper-proof screws come from a plant in Agawam, Mass., and are "exclusive for New York City," Mr. Salehi said.
Besides the super stacker, Mr. Salehi said, the city buys a "variety of sizes and styles" of chairs to fit the needs of students in different grades. Mr. Keller said the Education Department had bought smaller chairs, made of wood, for its youngest pupils. The department said it had also begun buying chairs from another company, Academia, in the last four years.
But education officials are pleased with the super stackers, Mr. Keller said, because the chairs are "very strong" and easy to clean. He said the school system -- which has an enrollment of about one million -- probably had "four million of them" in circulation.
"They last 5o or 60 years and they are probably replacing 50,000 a year," Mr. Keller said.
Still, Galen Cranz, a researcher and professor at the University of California, Berkeley, and author of the 1998 book "The Chair: Rethinking Culture, Body and Design," said she wished child movement were accorded more consideration in the standard designs.
Professor Cranz said schools in Denmark, where she has lectured, very often used chairs that were tall, with seats that could tilt forward or have front parts that slope forward. Those kinds of seats, she said, put children in a position "halfway between sitting and standing."
"There is a fairly long history of physicians being worried about what the chair is doing to little bodies," Professor Cranz said.
The school chair, she said, "has been replicated unconsciously, and if we bring even the tiniest bit of consciousness to it, we recognize it as problematic and it needs to be rethought."
Alain Delaquérière and Sheelagh McNeill contributed research.
This article originally appeared in The New York Times.