Like many older people, the sheriff in Cormac McCarthy’s No Country for Old Men thinks America is going to hell. Reflecting on the results of a survey of school teachers from the 1930s, he says: “The biggest problems they could name was things like talkin in class and runnin in the hallways. Chewin gum. Copyin homework. Things of that nature.” Forty years later, he finds, the same survey suggests a different world. “Well, here come the answers back. Rape, arson, murder. Drugs. Suicide. So I think about that.”

The sheriff considers the possibility that his impressions are just the eternal nostalgic grumbling of an older generation about the moral disintegration of the young. Then he decisively rejects it: “But my feeling about that is that anybody that cant tell the difference between rapin and murderin people and chewin gum has got a whole lot bigger of a problem than what I’ve got.”

In other words, the human impulse to romanticize the past doesn’t necessarily invalidate evidence of present decline. It’s worth asking if nostalgia might be skewing our perceptions, but sometimes, even after accounting for bias, a shift in values is undeniable.

I thought of McCarthy’s sheriff while reading Garrett Keizer’s new book, Getting Schooled: the Reeducation of an American Teacher. The premise of the book is simple but elegant: after a 14-year hiatus from teaching, Keizer returns to teach English at the high school in rural Vermont where he worked as a younger man. Have the kids changed, or just his perception of them?

Murder, drugs, and arson are mercifully absent from his story but many things are different than before. There’s more obesity, outfits on warm days are more revealing, smartphones and gadgets abound, and books are approaching extinction. One student says that he has never read a book in his life. Another student has one of Keizer’s colleagues deliver pizza to her during a class. His students seem unimpressed that he has written multiple books; when they learn that he appeared on The Colbert Report.

The school library resembles “a NASA control center in which the technicians occasionally break for a little light reading after lunch.” The volumes in the Library of America series have been demoted from the shelves to the floor, where they’re stacked into a pyramid that supports a few provocative titles like Pride and Prejudice and Zombies. Faulkner, Whitman, and Dickinson did not labor in vain; their books live on, horizontally, stacked like bricks in a display case.

Some colleagues are also different. Besides the teacher who delivers pizza, there’s one who proclaims proudly: “We’ve just about eliminated class discussions.” Instead of conversing, his students record their comments using an app and vote in class polls with their phones. Even television is passé; at one point Keizer tries screening a film only to notice that every kid but one is staring at a phone. It happens to be the moment in the film when a lawyer who has come to an Adirondack town for a case stares at the sky and asks: “What has happened to the children?”

To his credit, Keizer seriously entertains the possibility that the error is his and nothing has happened to the children. Perhaps from the benighted vantage of middle age, some changes that appear negative are actually signs of progress or are simply different manifestations of the same traits and tendencies kids have always shown.

In his earlier stint as a teacher, for instance, kids snuck out of class to smoke in the bathrooms; now they go to the bathroom when they want to text. It’s hard to feel much nostalgia for that particular aspect of the good old days.

But the analogy with smoking raises a deeper point that’s fundamental to his argument. Just as the economy profits from both the causes and cures of some health problems—smoking and chemotherapy, sugary sodas and diabetes medicine—schools sometimes pay companies for technologies that compound the very problems they pay other companies to solve. “We make kids illiterate by shrinking and/or wiring their libraries; then we build wired support centers to teach the illiterates how to read.”

The constant streams of evaluative data that teachers must generate present a similar irony. Every minute spent assigning numbers to student performance is time not spent imparting knowledge that could improve the skills the data is ostensibly measuring. A broader irony emerges when he attends town hall meetings and hears arguments against school funding that are themselves reflections of poor school funding. If some parents had gotten a stronger foundation in history, critical reasoning, and analysis, he thinks, they might pause to consider the potential objections to their claims.

Keizer is not advocating a ban on all new technology, the elimination of all evaluations, or mandatory daily reading of the Library of America authors. He’s skeptical of the common impulse to treat schools as magical realms where every variety of economic, social, and psychological problem are solved by the heroic ministrations of a superhuman pedagogue. There are limits to what schools can do, and what reforms within schools can do.

That said, his book makes an eloquent case that some of the most meaningful and important interactions between students and teachers occur when technology and evaluation are not involved. One of the great pleasures of his book is the narration of dozens of small but significant encounters with students.

There’s not an easy way to quantify the value of a conversation with a sophomore who has just decided to share her first poems with her English teacher. The poems were not mandatory, and the conversation occurs after class, so the event falls into a netherworld that the educational bureaucracy doesn’t recognize. But these are the moments that matter most to teachers and students long after the course material is forgotten.

Keizer’s method is anecdotal and narrative, but this gives it a subtlety and texture that data often lack. The school requires him to assign numerical values to almost every interaction with students; but reading about his difficulty quantifying the value of an exchange is far more valuable than trusting whatever number he might happen to pick.

It’s ultimately hard to say if McCarthy’s sheriff was right, but Keizer’s book illuminates many discouraging trends. In one sense, however, it’s a hopeful work. With humor and justified outrage, he reveals a powerful truth that often slips unnoticed through the increasingly tight nets of school reformers obsessed with technology and data collection. Sometimes old-fashioned conversation with a thoughtful and caring teacher—hard to quantify, impossible to automate—is the only thing that motivates students and teachers to keep going.