WASHINGTON, D.C. – Walmart is calling on Washington, D.C. residents to nominate a teacher to receive a $490 gift card – the average amount teachers allegedly spend out-of-pocket to stock their classrooms with supplies for the school year.

But the Washington Teachers’ Union thinks the effort is a “deceitful” and “bogus” scam that amounts to a “cynical coverup,” Fox 5 reports.

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Union brass are so worked up about the giveaway, they held a press conference Friday to urge members not to spend money at the retail giant.

The backlash, of course, has nothing to do with Walmart’s good will, but rather on the union’s self interest in maintaining a monopoly on public education that’s threatened by the company’s charitable arm known as the Walton Family Foundation.

“It is not true philanthropy when Walmart is cloaking that campaign under the auspices of wanting to help poor children with teachers buying school supplies,” WTU President Elizabeth Davis said.

“It seems to me that because Walmart wants to give this as a donation to students – that irrespective of conditions – we should accept it, we should want it,” Davis said. “I think that we need to be more conscious in that. We need to teach our students even gifts that appear to be free are not free.”

According to The Washington Post:

The union’s criticism of the Arkansas-based retailer stems from its concerns with the Walton foundation, one of the country’s biggest financial supporters of charter schools. The foundation says it has poured $1.3 billion into K-12 education over the past two decades, and it announced in January a commitment of $1 billion to help expand charter schools and other school-choice options nationwide.

In other words, because the Walton Family Foundation donates money to help give families an alternative to the public education system, which threatens the union’s grasp on schools in D.C., union officials view it as an evil entity hell bent on destroying public schools.

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“Walmart and the Walton Family have consistently sought to privatize our schools and destroy public education,” Davis said, according to the Washington Examiner.

About 44 percent of D.C. students attend charter schools, which are independently run public schools, and per-pupil funding sent along with them is cutting into the WTU’s bottom line, as most charter schools are not staffed by unionized teachers, the news site reports.

Regardless, union officials have long argued that independent charter schools are siphoning money from traditional, unionized public schools, despite the fact that many students perform better academically at charters.

“It’s a cynical coverup,” Davis said, according to the Post. “Walmart is privatizing all sectors, and we need to put a stop to it.”

Irene Holtzman, executive director of Friends of Choice in Urban Schools, countered the union’s claims about education funding, pointing out that charters are funded the same way as public schools.

“All of our schools are funded on a per-pupil basis,” she said. “Charters are not taking money away from DCPS.”

District officials, meanwhile, contend teachers in the district’s schools have plenty of resources to stock their classrooms.

“DCPS has increased our investments in schools every year for the last five years to ensure that our schools and classrooms have the materials needed for high-quality teaching and learning,” spokeswoman Michelle Lerner told the Post. “We also provide every teacher with $200 to supply their individual classrooms with school supplies.”

Parents, of course, think the union’s opposition to the giveaway is ridiculous.

“For one child it costs at least $150 to buy their school supplies, so if they’re willing to give $500 to a teacher who is doing a great job to help him or her supply their classroom, then I think it’s ridiculous for the teachers union to fight that,” one unidentified parent.

“It doesn’t matter if they’re giving it to a public school or a charter school, it should be about the children and not about their agenda.”