WASHINGTON D.C. – Standardized tests have never been popular with students, but now the assessments are also falling out of favor with a growing number of parents – much to the delight of the nation’s teacher unions.

The Associated Press reports that “a small but growing number of parents nationwide … are ensuring their children do not participate in standardized testing,” by keeping their children home on test days. The practice is becoming widespread enough for the media to give it a name: “the opt-out movement.”

When asked why they oppose the student assessments, “opt-out” parents offer reasons that read like talking points from a teacher union memo. Parents claim the standardized assessments are being unfairly used to evaluate teachers’ classroom performance and that they’re leading to a narrowing of the curriculum, commonly known as “teaching to the test.”

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They also say the tests are evidence that K-12 reform is allowing big corporations to control the education process.

New Jersey Parent Darcie Cimarusti told the AP, “My goal is that my daughters never take a standardized test. I see less and less value in it educationally and it is being used more and more to beat teachers over the head.”

Such comments must be music to the ears of teacher union leaders everywhere, who have been fighting against testing since the No Child Left Behind (NCLB) law tied federal K-12 dollars to standardized assessments.

The idea behind NCLB was that any school receiving financial assistance from the nation’s taxpayers should be held accountable for its ability to teach students basic skills. The only feasible way to measure that ability is through testing.

But activist teachers don’t like this setup because it forces them to stick to the assigned curriculum or suffer the consequences of bad job evaluations. That leaves them with fewer opportunities to push their ideological and political agenda in the classroom.

The unions also dislike testing because it helps school leaders identify which teachers aren’t very effective. That’s an affront to the teacher union belief that all educators are equal in skill, and should be treated (and paid) as interchangeable workers.

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Add it all up and it’s very understandable why the unions hate testing.

What’s distressing about the “opt-out movement” is that it’s proof some parents are falling for the unions’ anti-testing propaganda.

The AP reports that the anti-testing sentiment is popping up all across the country – from Seattle, Washington to Providence, Rhode Island. The movement appears to be growing, thanks to social media sites which allow unhappy parents to connect and organize protests.

The AP also notes there are no consequences for parents who keep their children home on testing day, which means this movement could keep growing.

As one anti-testing teacher told the news agency, “You can feel the momentum. I think we’re headed for a full-on revolt next year.”

Few educators or policy makers really love the idea of standardized testing, but it’s the only tool Americans have of ensuring that the nation’s schools – which consume huge sums of tax dollars – are actually helping prepare students for adult life.