WASHINGTON, D.C. – A new report by the left-leaning Center for American Progress shoots a massive hole in the union philosophy that increased spending equals increased student achievement.

The report, which analyzes 7,000 U.S. school districts by comparing spending to student achievement, shows “some schools get a lot more bang for their buck than others,” according to Ulrich Boser, the report’s author.

“This is not an argument to spend less on education but to make sure our education spending goes to improve student achievement,” Boser told the Huffington Post.

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In total, about a million American students attend unproductive schools, according to the study.

The findings are important because teachers unions across the country are relentless in pushing local school districts and states to increase education spending every year. The union lobbying is frequently successful, but the new funding is often wasted on union contract provisions and other expenses that have nothing to do with educating students, such as “release time” for union officials, unused sick day bonuses for school employees, and massive travel expenses for educators to attend “professional development” conferences at lavish resorts.

EAGnews has reported on many of these unnecessary expenses in large metropolitan school districts for a series titled “Where your school dollars go.”

“Many affluent districts, whether it was Scarsdale or Montgomery County, they didn’t do poorly. They have high achievement, but they’re also spending a lot, so that makes them less productive,” Boser told the Post. “We saw a lot of affluent areas don’t do great. They get middling results.”

What’s worse is that despite the fact that researchers took into consideration external factors like socioeconomic status of students and cost of living, the results show poor students who participate in the federal free and reduced-lunch program are twice as likely to attend a less productive district.

“Even more notably, black students are eight times more likely to be enrolled in one of the least productive districts than the most productive districts,” the news site reports.

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“What has been surprising is how little states have done in this space and how little districts have done,” Boser told the Post. “In education we don’t have that conversation. … We haven’t had that conversation about being more focused and getting a bigger bang for our buck.”

That’s likely because teachers unions have dominated the discussion on education for decades, and have shouted down anyone who points out that money doesn’t equal results as “anti-education” or “anti-teacher.”

The searchable database of Center for American Progress’ school district productivity study, as well as a copy of the group’s full report, is available on the Huffington Post website.