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  • Section I: Instruction


The RSU 21 Board of School Directors recognizes that there is a relationship between  class size and pupil achievement and that this relationship varies greatly across grade  levels, among subjects and by methods of instruction. Therefore, the recommended  class size in the elementary and secondary schools shall be determined by several  variables including grade level, subject area, nature of the pupils in the classroom,  nature of the learning objectives, availability of classroom space, instructional methods  and procedures used, skills and classroom space, strengths of the teachers and support  staff and budgetary constraints.  

Keeping all of these variables in mind, the following average class size ranges shall  serve as a general guide for the organization of classes in the elementary and  secondary schools.  

Grade level Class Size Range Recommended Avg. Size
Early K 12 – 16 15
Kindergarten +1 16 – 20 18
2 - 3 18 – 22 20
4 - 5 18 - 24 22
6 - 8 18 - 25 22
9-12 14 - 26 18-22

Higher class sizes will be allowed for the scheduling of large group instruction in grades  1-12 for special classes including: fine arts, physical education, instrumental and/or  choral music and other special instructional arrangements (e.g. lectures). Special  Education teacher-student ratios are to be in compliance with Special Education  caseload rules and State standards.  

Science laboratory or engineering and design classes shall comply with expectations for square footage per student.

When any elementary or secondary school class falls below or above the applicable  class size ranges, the Principal shall obtain permission of the Superintendent before  scheduling the class. The Superintendent’s decision in matters of this nature shall be  communicated to the School Board. In addition the Superintendent shall establish  procedures to review pre-registration information for secondary schools prior to deciding  staffing levels for the ensuing year.  

If any elementary or secondary school class size clearly exceeds (by 2 or more  students) the maximum range, the Principal shall consult with the Superintendent who  will make a determination as to whether the services of an additional teacher or teacher  assistant should be recommended to the Board. The Superintendent’s decision in  matters of this nature will be required to hire any additional staff members.  

Adopted: 6/13/94  

Amended: 12/8/97  

Amended: 04/08/02 

Amended: 12/20/21

  • Section I