Schools that enroll 90 percent or more non-white students spend $733 less per pupil per year than schools that enroll 90 percent or more white students, according to a report released Wednesday by the Center for American Progress.

These “racially isolated” schools make up one-third of the country’s schools. Nationwide, schools spend $334 more on every white student than on every nonwhite student.

According to the report, titled "Unequal Education," the traditional claim that variation in schools’ per-pupil spending stems almost entirely from different property-tax bases between school districts does not hold true. Rather, variation within a district can be largely attributed to district budgeting policies that fail to take into account teacher salaries. For instance, new teachers who often start out in high-need schools that enroll many students of color earn less money than veteran teachers located in more affluent, whiter areas.

“This leads to significantly lower per-pupil spending in schools with the highest concentrations of nonwhite students,” report author Ary Spatig-Amerikaner writes.

Spatig-Amerikaner also examines Title I of the Elementary and Secondary Education Act, a federal policy that is supposed to guard against within-district inequities. In order to receive Title I money, school districts must provide comparable educational services to both their high-poverty and low-poverty schools. However, the law stipulates districts exclude teacher salary differentials tied to experience when determining comparability compliance. Teacher salaries, of course, are often contingent on experience, and the author points out how this problem has frequently been referred to as the “comparability loophole.”

According to the report, high-minority schools, on average, boast 605 students. Thus, the average school would see an increase of $443,000 if per-pupil spending was brought to the same level as those schools that enroll very few nonwhite students.

As Spatig-Amerikaner reiterated in a press call to discuss her findings, this amount is enough to pay the average salary of 12 additional new teachers or nine veteran teachers -- a move that would go a long way in drastically reducing class size.

Also participating in the conference call, Rep. Chaka Fattah (D-Pa.) said the study adds to the “whole body of empirical data that shows that young people of color and poor kids in general are being shortchanged due to the way we fund schools.”

"We shouldn't have the kids needing the most help, being provided the least resources,” he said.

The report argues that Congress should close the comparability loophole, and outlines how the requirement should be changed in three phases when the Elementary and Secondary Education Act is reauthorized. According to the author, this change in federal law would affect about 3,386 districts, where 77 percent of all students attend school.

Fattah has proposed a bill that would do away with the federal loophole, and acknowledged the major hurdle to moving forward right now is the fact that the Elementary and Secondary Education Act has yet to be reauthorized.

In reading other people’s work, Spatig-Amerikaner said she found that district officials often do not realize that this problem of inequitable per-pupil spending even exists. They think that by providing the same number of teachers and the same student-teacher ratio at all of their schools, they are providing equitable services -- when in fact they should be looking at the total dollars spent at each school.

“A lot of school personnel have never had this data, so it’s almost not their fault that they don’t realize that this is a problem,” she said.

The data in question is school-level expenditure data -- including teacher salaries -- that was collected by the U.S. Department of Education for the first time ever in 2009, and released to the public in 2011.

“Many districts aren’t really aware that this problem exists, because they haven’t had the data until now,” Spatig-Amerikaner said.

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