Last year didn’t hold great news for District of Columbia public schools. Less than 20 percent of eighth-graders were proficient in either math or reading. Only 61 percent of District high school students made it to graduation.

Any city with levels of poverty like Washington (as many as 70 percent of students are low-income) is facing struggles that the suburban districts can never imagine. These are daily struggles for basic necessities, neglectful home situations, poor nutrition and the like. Yet is any city’s socio-economic status a reason to give up on 4 out of every 10 students?

Michelle Rhee didn’t think so. Ms. Rhee was the chancellor of the District’s public school system, appointed by Mayor Adrian Fenty in 2007. Ms. Rhee refused to accept D.C.’s poverty level as an excuse for failure. As she recently wrote in the Huffington Post, “Expectations of academic success for a child should never hinge on the circumstances of his or her birth.”

As a recent PBS Frontline special drove home, Ms. Rhee’s reforms were controversial, to say the least. She tied job evaluations to performance. In her three years, she closed nearly two-dozen half-empty schools, fired at least 36 principals, sacked 121 employees in her central office, and let go — while ignoring seniority — 400 underperforming teachers.

Ms. Rhee’s tough-love reforms came with results. For the first time in nearly 40 years, District students made more gains in math and reading than the gains of the nation at large. In Ms. Rhee’s three years as chancellor, elementary students’ reading proficiency was raised from 37 percent to 49 percent. Their math scores shot up from 26 percent to 49 percent as well.

There was similar upward movement with high school students’ test scores. Where reading levels were at 29 percent, by the end of Ms. Rhee’s term, they were at 41 percent. Math proficiency among the high school students increased from 23 percent to 40 percent.

Yet the backlash from her reforms was immediate and intense. Many claimed that she was too abrasive in instituting her changes. As The Washington Post reported: “Rhee is outspoken, impatient, apparently indifferent to the kind of tension and pushback that most in her line of work labor to avoid.”

Ms. Rhee’s critics protested more than her new direction. They questioned her integrity. Schools in the district were accused of cheating to achieve the results seen on exams. USA Today printed a piece reiterating that cheating had produced the higher test scores. The evidence cited was high erasure rates (changing answers from wrong to right) on the yearly tests at Noyes Education Campus and other District public schools.

Amid the cheating allegations, Vincent Gray unseated Mr. Fenty in the 2010 mayoral elections. After the election, Ms. Rhee agreed to leave her post as chancellor of the public school system.

It took three years, but on Jan. 8, the U.S. Department of Education closed the books on the cheating allegations. This investigation — along with several others at the local level — cleared Ms. Rhee’s schools of any widespread cheating. The scores — and the students’ improvements — were real.

Though the exoneration was too late for Ms. Rhee to continue her work in the District, her reforms have continued to influence the nation. Her most frustrating reform — tying teacher evaluations to student’s test scores — has been taken up by both sides of the political aisle nationwide. Teachers unions in Los Angeles, Boston and Chicago have all agreed to performance-based evaluations. New York City’s Mayor Michael Bloomberg wants his city to follow suit.

As cities across the nation follow Ms. Rhee’s example, last year’s 61 percent graduation rate serves as a painful reminder of why the District’s schools so desperately need reform — and what they lost by letting Michelle Rhee leave.

-Leslie Grimard is an assistant at the Heritage Foundation.