In what had been billed as a major speech on teacher education, U.S. Secretary of Education Arne Duncan last week reiterated concerns about the quality of the schools that produce a majority of the nation's teachers. But some observers said that by praising several new teacher-preparation initiatives, he struck a more conciliatory tone toward the institutions than he did in a speech on similar themes delivered less than two weeks earlier. Mr. Duncan delivered his speech, the capstone of several events focused on teacher preparation this month, before 900 educators gathered at Teachers College, Columbia University, in New York City. He called on programs to continue their improvement, saying most have not kept pace with a now decade-long focus on student outcomes. Using milder language than he did in the previous speech, he also said they are doing "a mediocre job" of preparing teachers for the realities of the profession. "America's university-based teacher-preparation programs need revolutionary change--not evolutionary tinkering," he said. Such changes should include a stronger preservice fieldwork component, a focus on subject-matter competency and classroom-management techniques, and state action to gauge the success of teacher college graduates in classrooms, Mr. Duncan said. He highlighted recent grants to bolster teacher "residency" programs and criteria in the $4 billion Race to the Top program that would help states boost teacher-training accountability. And in the only new measure announced, he said that the Obama administration would try to improve university-based preparation programs when the Elementary and Secondary Education Act comes up for renewal. Federal attempts to change teacher education have typically centered on the Higher Education Act, which lawmakers renewed last summer.