Schools, HIV testing, childcare and unemployment programs are all "under threat" as across-the-board cuts, known as sequestration, are scheduled to strike in January 2013, according to a new U.S. Senate report released Wednesday.

But Sen. Tom Harkin (D-Iowa), who chairs the senate appropriations subcommittee that oversees nonmilitary spending, chose to center a Wednesday hearing on these cuts specifically to examine how the billions lost could affect America's schools. "Education will provide an instructive example of the kinds of arbitrary cuts [that kick in] ... if sequestration goes into effect," Harkin said.

Three federal programs critical to education across the country -- Title I funds for poor students, state grants for special education and the Head Start public pre-school program -- would lose $2.7 billion over 10 years, the report predicted. As many as 15,000 teachers and aides could lose their jobs, and 10,000 special education workers could be laid off. Harkin based the report on the Congressional Budget Office's projection that sequestration would slash spending by 7.8 percent.

U.S. Secretary of Education Arne Duncan testified at the hearing, saying that the cuts, which go into effect should Congress fail to find another way to close the $1.2 trillion deficit, would be devastating. "To me, this fight is about so much more than education," he said. "Essentially we're just playing chicken with the lives of the American people."

The hearing comes two weeks after more than 3,000 advocacy groups representing recipients of non-defense discretionary spending wrote a letter calling for a "balanced approach" to fixing the deficit, and groups like the Center for Education Funding pushed hard to bring the issue into full view. Responding to a groundswell of advocacy by defense hawks, who have been making the case to exempt military spending from the cuts, education groups and Democratic senators like Harkin and Patty Murray (D-Wash.) wanted to show the American public the other side of the story.

At times, attendees drew the connection between education and national security, a link emphasized in a recent Council on Foreign Relations report by Joel Klein and Condoleezza Rice.

Harkin noted that, if defense spending is exempted, cuts to non-defense spending over the next 10 years would increase from 7.8 percent to 17.6 percent of current levels, which could mean that 217,000 children would lose Head Start funding and 34,000 teachers would be laid off.

"A strong national security system is about defense, but a strong public education system is about offense," Duncan said at Wednesday's hearing.

As officials in a congressional office building discussed the effects of further cuts, administrators and educators on the ground across the country are already coming to terms with what is often called the "new normal" in education spending, where austerity has forced layoffs and curricular trimming. A recent article in Education Next, an education journal run by Harvard University, found that "U.S. schooling may be on a historic glide path toward lower ... resources." From June 2008 to March 2012, the article notes, America's public schools have lost three percent of their total workers, or 250,000 jobs.

Class sizes, teachers have reported, are rising as school districts feel the sting of these cuts. Compounding those trends with federal cuts, Sen. Jack Reed (D-R.I.) noted, would be "doubling down" on local losses.

Some lobbyists in the education reform camp note that U.S. education spending has skyrocketed, while test scores have stagnated. Neal McCluskey -- an expert witness who serves as associate director for the Cato Institute's education center -- took this line, but a recent report from the nonpartisan Center on Education Policy shows that education spending has actually not grown at all as a share of the gross domestic product. In fact, as Wednesday's report notes, by 2021, all non-defense discretionary spending will represent only 2.8 percent of GDP.

Sen. Richard Shelby (R-Ala.), the only GOP member present, said he thought sequestration should be stopped but noted that, if federal education cash comprises only about 10.8 percent of all national education spending, then sequestration should only cause school districts to lose .84 percent of total funding.

But Billy Walker, superintendent of the Randolph Field Independent School District, which serves the population of an Air Force base near San Antonio, Texas, painted a different picture. Since military bases provide localities little in property taxes, his schools are more dependent on federal aid, which constitute fully half of his budget. He is more reliant on a type of federal funding known as Impact Aid, which compensates for a lack of local revenue, and which would be cut by $89.98 million nationwide under sequestration, according to Harkin's report.

"We're having to put more students in a classroom now," Walker said. "The concept of doing more with less is admirable, but there comes a time when there is not enough left to adequately and equitably educate the children of America."

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