ESSA, or Every Student Succeeds Act , passed last year by Congress, was an attempt to move away from the overly-prescriptive No Child Left Behind law and the even more prescriptive NCLB waivers imposed by Arne Duncan. Not only does ESSA authorize states to allow parents to opt their children out of exams with no fear of consequences, but it also specifically bars the Secretary of Education from telling a state how school participation rates must be factored into its accountability system, as the memo points out.
This provision appears to be written with the goal of forcing schools to try to force parents to make their children take the tests - lest the schools be counted as failing. Since many NY schools had opt-out rates of 20 percent or more, this would incorrectly identify many otherwise successful schools as low performing and thus in need of comprehensive improvement and support.
If and when we receive a response from the Commissioner or the Board of Regents we will let you know. Meanwhile, this memo could be useful for advocates and parents in other states who don't want their children's schools unfairly penalized on the basis of high opt-rates.