A half-million opt outs -- and that's in only 7 states that have reported! A typical U.S. student takes 112 standardized tests. "By contrast, most countries that outperform the United States on international exams test students three times during their school careers." 112 tests vs. 3 tests. Think something's wrong?

https://www.washingtonpost.com/local/education/at-least-500ooo-students-in-7-states-sat-out-standardized-tests-this-past-spring/2015/11/18/356db342-8e15-11e5-ae1f-af46b7df8483_story.html