Paul E. Peterson is a professor of government at Harvard University. In a recent op-ed at the Wall Street Journal, Peterson had few kinds words for Obama.

Paul E. Peterson: The Obama Setback for Minority Education

Should federally mandated school accountability and testing requirements be abandoned? With Congress actively considering a major revision of No Child Left Behind, that question has moved to the top of the national education agenda. The Obama administration, teachers unions and some Republicans are joining forces to gut core provisions of the education law that was one of the Bush administration’s crowning achievements.

No Child Left Behind, which began in 2002, focused on the low performance of African-American and Hispanic students. It required that all students, no matter their race or ethnicity, reach proficiency by 2014. Since minority students had the longest road to travel, schools placed special emphasis on their instruction, and measured the quality of their instruction by ascertaining their performance on standardized tests.

Each school was required to report annual test-score results for every student in grades three through eight. (High-school students took only one test in four years.) Although all schools were tested, No Child requirements bore most heavily upon schools that received federal compensatory education dollars, which typically had substantial percentages of minority students.

In 2008, Democrats secured major contributions from teacher organizations by campaigning aggressively against No Child’s testing and accountability provisions. “We can meet high-standards without forcing teachers and students to spend most of the year preparing for a single high-stakes test,” candidate Obama insisted.

After winning the presidency, Mr. Obama halted enforcement of most of No Child’s key provisions and offered waivers to states that signed up for more lenient rules devised by the Education Department. So far, waivers have been granted to 40 states. The latest bill promoted by the Senate education committee calls for testing but allows states to let students submit “portfolios” or “projects” in lieu of the standardized tests required by the original law.

Now that No Child itself is under reconsideration, it is worth asking if the law actually worked. Did minority-student performance improve during the years when its provisions were strictly enforced? And what gains have been registered since Mr. Obama allowed enforcement to wither?