According to Article 5.A.3. DUTIES:
5.A.3. Teachers shall not be required to perform custodial services.
5.A.3.a. Classrooms shall be clean and sanitary.
5.A.3.b. Teachers will require their students to maintain neat, clean and orderly classrooms by performing traditional housekeeping chores, such as erasing the chalkboard and picking up papers.
5.A.3.c. Teachers will secure their rooms in a manner developed jointly by the faculty and administration of the school.