State law addresses vision screening.
105 Code of Massachusetts Regulations 200.400 Vision and Hearing Screenings
(B) The school committee or board of health shall cause the vision of each student in the public schools to be screened in the year of school entry, annually through grade 5 (or by age 11 in ungraded classrooms), once in grades 6 through 8 (or ages 12 through 14 in ungraded classrooms) and once in grades 9 through 12 (or ages 15 through 18 in ungraded classrooms). The vision of each student shall be tested by means of the Massachusetts Vision Test or other comparable method approved by the Massachusetts Department of Public Health.
Responsibilities of School Health Services
"Oversee the mandated screening programs consistent with Massachusetts General Law. Under M.G.L.c.71 s.57, these include Body Mass Index (BMI),vision, hearing and postural screenings." - I checked the law, this is for every student at request of the parent