As testing season draws to a close, a whole new crop of issues is just bubbling up.

A few weeks ago, all 280 juniors at Nathan Hale High School in Seattle chose not to take a Common Core-aligned standardized test because they didn't think it accurately measured their skills.

Even though those students won't receive any credit for the test, known as the Smarter Balanced Assessment, most of them don't need it to graduate, according to Seattle Public Schools. That district is one of many taking a stance in a growing movement against high-stakes testing.

Just last year, the school board in Lee County, Florida, voted to eliminated the state and national education assessment tests. Even though the vote was reversed the next day, it has stirred up a "very potent movement," said Bob Schaeffer, public education director of FairTest, a national organization that advocates for test reform.

And earlier this month, the Illinois House approved a bill that would allow students to opt out of state assessment tests with written permission from a parent or guardian. Chicago Public Schools initially tried to nix giving new Common Core-based standardized tests this year, a decision the district reversed after the Illinois State Board of Education threatened to withhold funding.

So why are these tests leading to such an uprising? Schaeffer calls the movement is a response to "testing overkill" from students, teachers, administrators and community leaders.

"Across the country, school districts are taking stances against testing misuse and overuse, calling for fewer tests and less consequences attached to them," he said.

The boycotts also stem from student and parent anxiety about new, more rigorous tests — many of which are aligned with Common Core — said Kelly Pollitt, associate executive director of policy, public affairs and special projects for the National Association of Elementary School Principals.

"Anytime you have something that's new and different, people get a little worried," she said. "It just happens that the new standards and assessments are happening on a much bigger scale than they ever have."

State-mandated standardized tests date back to No Child Left Behind, President George W. Bush's 2001 reauthorization of the Elementary and Secondary Education Act of 1965, which requires annual state assessments primarily to ensure a good education for disadvantaged and minority children. The original goal was to ensure students were hitting a proficiency bar.

Other purposes of the tests have included evaluating teachers and even determining whether a student graduates or gets promoted to the next grade level.

"In the current situation, when one big test has so much attached to it, it results in dumbing down teaching and learning," Schaeffer said, referring to the phenomenon of "teaching to the tests" taking precedence over a focus on general instruction. He believes the tests should count as only one factor for measuring student achievement.

In the meantime, it may not be as simple as just opting out in some districts — as they are not letting students do so, despite pushback from parents and advocacy groups, Pollitt said. She noted that federal law requires 95 percent of students in districts must participate in assessments.

"Otherwise, it just creates a mess for states and districts measuring student progress and accountability systems," she said. "When you opt out of assessments, it's really a disservice to the students."

Districts across the nation are addressing the issues in different ways, including community meetings to educate parents to clear up any misunderstanding of the assessments and their purpose, Pollitt said.

However, a bipartisan rewrite of the NCLB law could change up the testing landscape. The bill, which is likely to be passed soon in the Senate, would remove some of the "high stakes" in testing by eliminating all federal required consequences for standardized tests — which FairTest supports, Schaeffer said.

"We want better forms of assessment," he said. "Tests that would look at not how well kids fill in bubbles, but the work they do over time."