Common Core continues to create unintended consequences on America’s educational system.

The numbers are in, and it looks like there is a jump in the number of students opting out of standardized exams to protest the “toxic culture of testing.”

When it comes to standardized tests, parents across the country are (a) concerned; (b) demanding change; (c) pulling tens of thousands of children out of the exams; or (d) making themselves heard at the top levels of government.

Answer: all of the above.

The backlash is kicking into high gear this spring as millions of students start taking new, more rigorous exams aligned with Common Core standards. Officials say the high-stakes assessments are crucial to evaluating student progress and competitiveness.

But a growing cohort of parents, students and teachers are rebelling against what they consider a toxic culture of testing. And officials, including U.S. Education Secretary Arne Duncan, have begun to listen as the grassroots movement engineers a series of high-profile rebuffs:

— Thousands of Colorado high school seniors walked out on new state-mandated science and social studies tests last fall.

— An Ohio middle school teacher published a letter calling state officials “bullies” for printing a pamphlet that warned of wide-ranging consequences if students sit out exams.

— At least 93 students at a single Philadelphia middle school are declining upcoming tests in a city that saw only 20 students districtwide sit out the exams last year.

The polite phrase for the burgeoning movement is “opt out.” But testing opponent Morna McDermott, a Baltimore-area mother of two, puts it more plainly: It’s a testing refusal movement — or a boycott.

“We’re not doing this willy-nilly because we’re a bunch of disgruntled soccer moms,” said McDermott, who belongs to the national United Opt Out movement and refuses to let her children participate in Maryland’s assessments. “This policy is harmful to our society, to our schools, to our teachers and to our children.”