Multi-Age Groupings in Montessori Classrooms

By: American Montessori Society

Updated June 6, 2019 to include information about the AMS Pathway of Continuous School Improvement. Originally published November 4, 2014.

At a meeting held Saturday, October 25, 2014, in Philadelphia, PA, the American Montessori Society Board of Directors voted to approve the recommendation made by the AMS School Accreditation Commission (SAC) for multi-age groupings in AMS-accredited schools and schools seeking AMS accreditation. The recommendation defines the requirements for multi-age groupings (see chart) and specifies that there will be no option for a variance to be granted for classrooms with alternative groupings.*

The work of the commission was informed by a Multi-Age Task Force that was convened in fall 2013, with members drawn from SAC and the AMS Board, and the chair of the Teacher Educators Section. Also considered were opinions shared by AMS members, writings by Maria Montessori and Nancy McCormick Rambusch, current research, and best practices of other accreditation agencies.

AMS-Approved Multi-Age Groupings

Infant & Toddler  Children from birth – age 3 may be grouped in varying multi-age configurations.  A stand-alone classroom serving only 3-year olds does not satisfy this requirement
Early Childhood 3-year grouping within the range of ages 2.5 – 6
Lower Elementary Ages 6 – 9
Upper Elementary Ages 9 – 12
Elementary I – II Ages 6 – 12
Secondary Ages 12 – 14, 14 – 16, 16 – 18 or ages 12 – 15, 15 – 18


Of utmost consideration and importance was the understanding that multi-age groupings are central to how Montessori is delivered in our schools, how teachers are prepared by our teacher education programs, and which schools are available as practicum sites for our adult learners. We recognize that the decision may have ramifications for schools that are not yet accredited by AMS, and that some schools will be unable to meet this multi-age requirement for accreditation due to state or local regulations. We would invite schools in this situation to join the Pathway of Continuous School Improvement, where we have allowed for schools to be exempt from this standard when mandated by law. These schools may attain as high as Step 9 on the Pathway and it is our hope that they may use school accreditation as a tool to convince their state regulators of the necessity to allow multi-age groupings.

In this age of increased attention to school choice, standards of quality rating by states, and increased scrutiny of teacher preparedness and quality, defining and adhering to quality is of the utmost importance. AMS is here to support our community as we navigate these challenges, find ways to validate quality schools and teacher education programs, and deliver exceptional education. We believe that clear communication of and adherence to Montessori principles and standards are essential if Montessori is to be become widely accepted as a quality education choice.

Schools with multi-age grouping variances previously approved by the School Accreditation Commission are grandfathered such that they may maintain the age-grouping(s) for which the variances were granted with a designation that they adhere to a non-traditional Montessori age grouping.