NEW YORK (MainStreet)—With the clock running out on the congressional summer session, a group of education and student leaders asked the Senate to discard a short-term cap on interest rates in favor of long term reductions in cost that would make higher education more affordable.

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In a joint letter, leaders of the six organizations told the Senate that "students should not be seen as a cash cow" in the continuing debate over student loan interest rates—rates that are seen as a significant source of revenue for the Department of Education. In March, the Congressional Budget Office found that the government will save $61 billion through the Direct Student Loan program, which has prevented banks from collecting fees from federal loans since 2010.

In the letter, addressed to Senate Majority Leader Harry Reid (D-Nev.) and Minority Leader McConnell (R-Ky.), the group - which includes the American Federation of Teachers, the National Education Association, the Educational Trust, the U.S. PIRG and the United States Student Association - discusses why many long-term proposals being considered would leave students worse off than if Congress did nothing at all.

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In addition, the letter, which can be found here , spells out how "budget-neutral" proposals lower interest rates for today's students by charging tomorrow's students significantly more, and claims that none of these proposals is based on the government's actual cost of borrowing and running the loan program. It concludes: "We need a deal that is based on research and evidence and is good for ALL students in the short and long term, not a deal for a deal's sake. Students deserve better."

Hyperbole aside, the group hit on a prevailing theme. "While the economy demands that more and more Americans get a post-secondary degree or credential, a college education has become less and less affordable. What the country needs now is leadership to reduce the actual costs of higher education, not make it more expensive." Spokespersons for senators Reid and McConnell could not be reached for comment.

The group has two essential questions. The first: how much does it cost to run the federal student loan program? The second: what is the government's cost of lending? Many students and student groups agree that a market-based rate is reasonable, but it must be tied to the government's cost of lending and it must have a meaningful cap to protect students from high interest rates. A Department of Education spokesperson could not be reached for comment.

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Ultimately, the group may be ready to settle for half a loaf in the form of a roll back of interest rates for Stafford loans to 3.4% from 6.8% for another year--a rate that Senate Democrats came very close to compromising on last week. Lisa Lederer, Washington, D.C.-based spokesperson for the group, had no comment on possible resolutions. Congress summer recess is set to begin on August 5.

"As negotiations continue," the group concluded, "Congress must address these questions. If it cannot, then it should pass a short-term, one year extension of the 3.4% rate for low-income borrowers, and revisit the debate over comprehensive reform during reauthorization of the Higher Education Act."

According to a Senate source, Senator Tom Harkin (D-Iowa) chair of Senate committee on Health, Education and Labor, has plans to re-authorize the Higher Education Act, first signed in 1965, by year end.

--Written by John Sandman for MainStreet