Los Angeles ? After three terms as Colorado’s governor and a stint herding cats — he was Democratic Party chairman — Roy Romer was 71. A mountain climber who had scaled the Matterhorn, and a glutton for punishment, he decided it was time for “a hard job.” He found one.

Now in his third year as superintendent of this city’s schools, Romer is the Don Rumsfeld of domestic policy. Too old to aspire to another job, he has the impatience of someone who, unlike many in government, wants to do something, not just be something.

His aim is to change the school system’s “culture of low expectations,” the “belief system” of those who “don’t believe everyone can learn.” Too many educators, he says, believe only in aptitudes, whereas “we believe in effort-based education. All children can learn. Effort counts.”

The polyglot district’s students are 72 percent Hispanic, 12 percent African-American, 9 percent white. Two-thirds of the students in grades K through 3 come from homes in which English is not the first language. The district, where students speak 72 languages, has more students — about 750,000 — than 27 individual states have, and a budget larger than Colorado’s.

But because the schools are underfunded, they also are overcrowded. His almost $10 billion school construction program, one of America’s largest current public works projects, is beginning to address the shortage of 200,000 seats for students if Los Angeles is to ever again have a normal school year — one with schools not in session year-round.

Building 150 new schools means transforming that many neighborhoods. And Romer subscribes to the axiom that we shape our buildings, and then they shape us. He thinks smarter physical arrangements can change the relationship — professional and personal — between teachers and students.

Too many Los Angeles high and middle schools are too big. Many have more than 5,000 students. Romer wants schools configured in more manageable subunits — say, 500 pupils — so teachers can know students for four years “and everybody owns the results.” In the Army, Romer says, “if someone can’t march, the unit’s response is, ‘Hey, you’re embarrassing us.”‘ He wants schools to feel similarly implicated in each student’s performance.

Although many children are already performing well below grade when they arrive at kindergarten, the district has achieved dramatic improvement in elementary school test scores. Romer thinks this is because an elementary school “is a small learning community.” More elementary school teachers than high school teachers want to be what they are, because elementary school teachers have the satisfaction of what Romer calls “ownership” of the child. Secondary school teachers are more oriented to the subject matter, and if a child fails math or science, well, the child did not have the suitable background, which is someone else’s fault.

The school district’s dramatic improvement in elementary school scores is the result of a rigorous curriculum featuring instruction in phonics. Plus what Romer calls “really trained teachers — trained after they leave school,” trained especially in how to teach reading. Plus teaching coaches in classrooms. Plus — Romer calls this “the real culture-changer” — diagnostic measurement every 10 weeks that returns results in 24 hours, revealing what homework is needed, and shaping classroom instruction for each child during the subsequent 10 weeks.

To those who criticize “teaching to the test,” Romer responds: That is what flight schools do. Because we take flying seriously. He likens testing throughout the school year to what many football teams now do by studying photos during the game, when diagnosis is immediately useful.

Romer, whose reformist agenda has a Rumsfeldean breadth, believes the six-hour school day is too short. So is the 180-day (163 for 300,000 Los Angeles students) school year, which is a relic of 19th-century America, when children were needed on ranches and farms in late spring and early autumn. In Japan and Europe the school year is 60 days longer. And Romer thinks it is unwise to base teachers’ pay on length of service plus post-B.A. credentials rather than on students’ cognitive accomplishments, plus peer review by other teachers.

Most contemporary policy arguments — how many foreign interventions are too many, or how much deficit is too much — are questions of prudence. The education of poor children is a question of justice. Romer is, strictly speaking, a radical — one who would go to the roots of things. An American rarity, his radicalism is commensurate with America’s glaring failure to equip poor children — none of whom asked to be here — to thrive here.

– George Will is a columnist for Washington Post Writers Group.