Mass. Gen. Laws ch. 149, § 95

If a minor 16 years of age or older fails to meet the requirements for the completion of the sixth grade, a person shall not employ that minor while a public evening school is maintained in the town where the minor resides or in the town of employment if he is authorized to attend a public evening school therein, unless that minor is a regular attendant at the evening school or at a day school and presents to his employer each week a school record of his attendance. When his record shows unexcused absences, his attendance shall be deemed to be irregular and insufficient, but the person authorized to issue permits for employment, or teachers acting on his authority, may excuse justifiable absence or waive the school attendance requirements if, in the opinion of the school physician, the physical or mental condition of that minor is such as to render attendance harmful or impracticable.