The first Thursday in June in each year, except in those years when the first Thursday in June occurs in the same week with Memorial day, and in such years the second Thursday in June, known as anniversary day, and celebrated in commemoration of the organization of Sunday schools, is hereby made and declared to be a holiday for pupils in all the public schools in the borough of Brooklyn and in the borough of Queens, city of New York, and pupils shall not be required to attend the public schools in such boroughs on such day.
N.Y. Educ. Law § 2586