First, great teachers tended to set big goals for their students.

Superstar teachers had four other tendencies in common: they avidly recruited students and their families into the process; they maintained focus, ensuring that everything they did contributed to student learning; they planned exhaustively and purposefully—for the next day or the year ahead—by working backward from the desired outcome; and they worked relentlessly, refusing to surrender to the combined menaces of poverty, bureaucracy, and budgetary shortfalls.

When her fourth-grade students entered her class last school year, 66 percent were scoring at or above grade level in reading. After a year in her class, only 44 percent scored at grade level, and none scored above. Her students performed worse than fourth-graders with similar incoming scores in other low-income D.C. schools. For decades, education researchers blamed kids and their home life for their failure to learn. Now, given the data coming out of classrooms like Mr. Taylor’s, those arguments are harder to take. Poverty matters enormously. But teachers all over the country are moving poor kids forward anyway, even as the class next door stagnates. “At the end of the day,” says Timothy Daly at the New Teacher Project, “it’s the mind-set that teachers need—a kind of relentless approach to the problem.”

t year’s end, teachers who score below a certain threshold could be fired.

What did predict success, interestingly, was a history of perseverance—not just an attitude, but a track record. In the interview process, Teach for America now asks applicants to talk about overcoming challenges in their lives—and ranks their perseverance based on their answers.

Gritty people, the theory goes, work harder and stay committed to their goals longer

This year, Teach for America allowed me to sit in on the part of the interview process that it calls the “sample teach,” in which applicants teach a lesson to the other applicants for exactly five minutes. Only about half of the candidates make it to this stage. On this day, the group includes three men and two women, all college seniors or very recent graduates.

But if school systems hired, trained, and rewarded teachers according to the principles Teach for America has identified, then teachers would not need to work so hard. They would be operating in a system designed in a radically different way—designed, that is, for success.

five observation sessions conducted throughout the year by their principal, assistant principal, and a group of master educators.

are almost never dismissed.

But this tradition may be coming to an end. He’s thinking about quitting in the next few years.