Under the plan, the federal government would require states to issue report cards for teacher preparation programs. (Paige Trisko/AP)

The Obama administration unveiled a proposal Thursday to regulate how the country prepares teachers, saying that too many new K-12 educators are not ready for the classroom and that training programs must improve.

Under the plan, the federal government would require states to issue report cards for teacher preparation programs within their borders, including those at public universities and private colleges, as well as alternative programs such as those run by school districts and nonprofits such as Teach for America.

The rating systems, which would need approval by the Education Department, would for the first time consider how teacher candidates perform after graduation: whether they land jobs in their subject field, how long they stay and how their students perform on standardized tests and other measures of academic achievement.

“Nothing in school matters as much as the quality of teaching our students receive,” Education Secretary Arne Duncan told reporters Thursday. “We owe it to our children to give them the best-prepared teachers possible.”

It will be years before any changes take effect. The administration will take public comments for 60 days, and it plans to issue new regulations by September 2015. But states would not be required to issue report cards for teacher programs until April 2019, well into the next administration.

Arthur Levine, former president of Teachers College at Columbia University and a critic of teacher preparation programs, said the country needs urgent action. “Our colleges and universities have waited far too long to transform these programs to meet the needs of both today and tomorrow,” he said

Terry W. Hartle, senior vice president at the American Council on Education, which represents colleges and universities, said the move is “a significant expansion in the federal role overseeing state government. But it may well change considerably before it becomes final.”

Some professions have standardized systems and exams to ensure consistency. Medical students, for example, undergo a four-year program and a residency before taking a state licensing exam and national board exams, all designed so that new physicians have the same essential knowledge and practical skills.

Teacher preparation programs vary from school to school, and states set licensing requirements.

A 2007 McKinsey study found that 23 percent of U.S. teachers graduated in the top third of their class, while 100 percent of teachers in Singapore, Finland and other nations whose students lead the world on international exams finished near the top of their classes.

A shortcoming of the programs is that few track how their graduates perform in the classroom, Duncan said. The proposed regulations would create a feedback loop for teacher candidates choosing among programs and school districts looking to hire new graduates, he said.

States would be required to judge the quality of an education program in large part by tracking the performance of a newly minted teacher’s students on standardized tests. That idea triggered immediate protests from teachers unions, which argue that student test scores are not an accurate measurement of teacher effectiveness.

“There’s no evidence these regulations will lead to improvement and plenty of reason to believe they will cause harm,” said Randi Weingarten, president of the American Federation of Teachers, adding that teacher prep programs might avoid placing graduates in struggling schools where test scores tend to be lower and teacher turnover higher.“Due to the focus on K-12 test scores, the very programs preparing diverse teachers for our increasingly diverse classrooms will be penalized.”

Becky Pringle, vice president of the National Education Association, said her union recognizes the need for better teacher training, but she also slammed the “inappropriate” use of test scores to judge teacher preparation. “Too many teachers are saying they are unprepared for the realities of the classroom and that teacher preparation, licensure, and induction standards must improve,” she said.

This is the second time the department has tried to regulate how schools prepare teachers. An earlier effort collapsed in 2012, after negotiators could not agree whether test scores are a valid way to assess teacher quality.

Under the proposal, states would rate programs as “low-performing,” “at-risk,” “effective” or “exceptional.”

If a program is “low-performing” or “at-risk” for two consecutive years, it will lose federal Teacher Education Assistance for College and Higher Education, or TEACH, grants, which give up to $4,000 a year to teacher preparation candidates who agree to work full time in high-need fields and struggling schools for at least four academic years. In fiscal 2014, the Education Department awarded about 34,000 grants worth $96.7 million under the program.

Charles Barone, policy director for Democrats for Education Reform, said that improving the education schools’ quality will prevent future problems.

“They could save a lot in the long run if they just got the training right from the get go,” he said.

“Too many people are graduating who aren’t prepared to teach. Then you get bad instruction for the kids. And we try to remediate that,” Barone said. “You’d do less of that and disrupt fewer lives if you just got it right from the beginning.”