Christopher Gregory/The New York Times

President Obama urged law schools on Friday to consider cutting a year of classroom instruction, wading into a hotly debated issue inside the beleaguered legal academy.

“This is probably controversial to say, but what the heck. I am in my second term, so I can say it,” Mr. Obama said at a town hall-style meeting at Binghamton University in New York. “I believe that law schools would probably be wise to think about being two years instead of three years.”

The president’s surprising remarks, made while discussing how to make education more affordable, come at a time of crisis for law schools. With an increasing number of graduates struggling with soaring tuition costs, heavy student debt and a difficult job market, a growing number of professors and administrators are pushing for broad reforms in legal education.

“We academics toil in the wilderness,” said Samuel Estreicher, a professor at the New York University School of Law leading a movement to permit students to take the bar exam and practice after two years. “It is great to have the president join the cause.”

Mr. Obama has plenty of credibility inside the legal world. After graduating from Harvard Law School, where he served as the president of the Harvard Law Review, he taught constitutional law at the University of Chicago from 1992 until his election to the Senate in 2004.

On Friday, he questioned the utility of a third year of classes and suggested that students use their final two semesters to gain work experience. “In the first two years, young people are learning in the classroom,” Mr. Obama said. “The third year, they’d be better off clerking or practicing in a firm even if they weren’t getting paid that much, but that step alone would reduce the costs for the student.”

He acknowledged that eliminating a third year could possibly hurt a law school’s finances and ability to maintain a strong faculty. “Now, the question is,” Mr. Obama said, “can law schools maintain quality and keep good professors and sustain themselves without that third year? My suspicion is, is that if they thought creatively about it, they probably could.”

The president was preaching to a growing choir of law school faculty.

Earlier this year, New York University held a symposium on reforming law school. Professor Estreicher argued that making the third year optional would reduce the cost of a legal education while encouraging clinical work outside the classroom. The school recently revamped its third-year curriculum with a focus on foreign study and specialized concentrations.

William D. Henderson, an Indiana University law professor who has also pushed for changes, welcomed Mr. Obama’s remarks. But he expressed relief that law school wasn’t two years when he attended the University of Chicago, graduating in 2001.

“I took Obama’s class in my third year,” Mr. Henderson wrote in an e-mail. “I would have missed out!”