Standards for AMI Montessori Classrooms

AMI pedagogical standards maintain the level of excellence that Maria Montessori envisioned. Established by the AMI Scientific Pedagogy Group, the standards insure that each school offers programs for their children that allow for their full intellectual, social, and psychological growth and that the approach is consistent with what is presented in AMI training courses worldwide.

The Teacher
There will be one AMI trained teacher at the appropriate age level in each class.

Each class may have one non-teaching assistant. Should local regulations make it necessary to have more than one aide, he/she should be a non-teaching aide and should assist the directress by making materials, supervising outdoor activities, and assisting with field trips or “going-out”.

The Materials

Each classroom must be equipped with a complete set of Montessori materials from an AMI approved manufacturer. There can be slight differences in the materials presented on AMI training courses, therefore, a “full set” of AMI materials includes those materials needed by the AMI trained teacher to present lessons given in their albums and according to their training.

The following companies manufacture materials according to detailed blueprints provided by AMI:

Nienhuis Montessori by Heutink International

Gonzagarredi Montessori

Matsumoto Kagaku Japan

Agaworld Montessori

NOTE:  Not all of the materials in these companies’ catalogs are AMI-approved materials.  Please, look for the AMI logo next to those approved by AMI.

Digital Materials

AMI Digital provides a large range of digital Montessori materials including charts, classified cards and publications.  The materials can be purchased and downloaded ready to print.

The Classes

Number of Children
Classes include a well-balanced division of ages as well as an appropriate number of children to ensure social development:

Nido:  maximum of 9 children

Toddler: 10-14 children

Primary: 24-35 children

Elementary: 24-35 children

Age Range
Classes are made up of children in the following age ranges (ages listed are approximate):

Nido (infant environment): 2 months to 12/15 months

Toddler Community: 12/15 months (walking well) to 3 years

Primary class: 3-6 years

Elementary class: 6-9 & 9-12 years, or 6-12 years

Uninterrupted Work Period
Classes are scheduled five days per week (unless specified otherwise) with substantial uninterrupted work periods every day:

Toddler: 2 hours per day, at least four days a week

Primary: 3 hours per day every morning for all children, and 2-3 hours per day every afternoon for the older children (extended day)

Elementary: 3 hours per day every morning, and 2-3 hours every afternoon with an allowance of one morning or afternoon work cycle for specialty programming

A consultation by an AMI trained consultant is required at least once every three years.

AMI School Recognition Status
The AMI school recognition program was initiated in the United States to assist parents in assessing whether schools are following Montessori’s principles and practices in their original integrity and completeness. It is upon these standards that AMI recognition is granted.

A school applies to become an AMI-Montessori school annually. The recognition status is based upon the training of their teachers as well as their compliance with the pedagogical standards. There are three different status levels offered:

AMI Recognized
To receive an AMI Certificate of Recognition a school must be in compliance with all of the AMI standards.

For schools that do not meet all of the standards, AMI/USA offers two alternatives:

AMI/USA Affiliated
To qualify for Affiliated Status, two out of three classrooms or three out of four classrooms, or multiples thereof, must have AMI-trained teachers at the appropriate level.  Additionally, the school must meet all other AMI standards.

AMI/USA Associated
Schools can qualify for Associated status when they are in the developmental process and are striving to meet all of the AMI standards within three years.  An exception to the three-year time limit is when low enrollment is due to circumstances beyond the control of the school, in which case the three-year time limit can be exceeded with annual review and evaluation.

Public schools may qualify for Associated status when 50% of the teachers hold AMI diplomas and when at each level there is at least one AMI teacher holding a diploma for that level.

Grace Period
Affiliated and associated schools are granted this status based on the fact that they are aspiring to become AMI recognized schools. These schools are given a grace period of up to three years in which to meet the requirements for AMI recognition.

AMI Trained Teacher*
Non-teaching Assistants
1 per 5 or 6 children (toddler)**
1 per 3 children (nido)
Consultation visit at least once every three years
Complete set of Montessori materials from an AMI approved manufacturer
Children of a mixed three-year age group, including a well-balanced division of ages
(ages listed are approximate)
Parent/Infant or Nido:
2 months to
12/15 months
12/15 months
to 3 years
3 to 6 years
6 to 9, 9 to 12,
or 6 to 12 years
Classes with an appropriate number of children to ensure social development
10-14 children (toddler)
24-35 children
24-35 children
work cycles (uninterrupted)
Toddler only: 2 hours per day,
4 days per week
3 hours per day,
5 days per week
prolonged work periods,
5 days per week***
work cycles

Not required
2-3 hours per day,
5 days a week
prolonged work periods,
4 days per week***
* Some schools are temporarily unable to meet this requirement. If a school is unable to meet this requirement, they may apply for Affiliated or Associated status.
**In the Toddler Community, this number refers to the ratio of all adults to children. In a class of 10 children, for example, there should be one trained adult and one non-teaching assistant (one adult per 5 children).
***Elementary Work Periods: At the elementary level, prolonged uninterrupted work periods are required every morning and afternoon, with an exception being one work period a week which may be left free to accommodate additional subjects. In practical terms, what this means is that for each elementary class, one work period each week may be set aside for a special subject such as foreign language or physical education. Out of a possible ten work periods per week, nine must be reserved for Montessori work. Other special subjects can be scheduled in such a way that there is still an uninterrupted work period.