Training and certification pathway comparison
For a prospective Montessori teacher, the choice of training pathway is partly pedagogical and partly practical: cost, time, location, and how portable the credential needs to be. This page sets out what’s actually different between the main routes, without treating any one of them as the “correct” path. See Choosing a School for the parent-facing version of this comparison.
AMI (Association Montessori Internationale)
AMI runs a single global syllabus, maintained centrally from its Amsterdam headquarters, with four separate age-specific diplomas:
| Diploma | Age band | Typical training hours |
|---|---|---|
| Assistants to Infancy | 0–3 | ~650 hours |
| Early Childhood | 3–6 | min. 400 hours |
| Primary/Elementary | 6–12 | min. 440 hours |
| Adolescent | 12–18 | ~740 hours |
Training is available as one intensive academic year or spread across modular summer/holiday sessions, but always requires in-person, supervised teaching practice. It cannot be completed entirely online. Because the syllabus is set centrally, diplomas from different training centres follow the same syllabus, which matters to anyone who expects to work internationally. AMI describes its diploma as “respected worldwide for its authenticity, high standards, and quality”, and says its diploma courses are examined by external examiners it appoints, “who serve to maintain the high standard and integrity of AMI course programmes” (AMI’s own website, montessori-ami.org, training pages checked 11 October 2026). That is AMI’s own description; this site has not reviewed evidence on whether the training route makes a difference to classroom fidelity or to children’s outcomes (see the gaps listed in the Annotated Bibliography).
AMS (American Montessori Society)
AMS takes a structurally different approach: rather than running one centralised curriculum, it accredits a network of independently operated Teacher Education Programs (TEPs), each of which designs its own course within AMS standards. Typical programmes run one to two years, often blending in-person and online coursework with a practicum (some Early Childhood programmes run around nine months), and AMS requires 50 hours of continuing education every five years to keep a credential active.
The practical consequence: more variety from one AMS-trained teacher to the next than you’d find across AMI, more flexibility in format and pace, and, depending on the specific TEP, sometimes more deliberate blending of Montessori method with mainstream school conventions such as letter grades or standardised assessment.
MACTE accreditation: a cross-organisation baseline
MACTE (Montessori Accreditation Council for Teacher Education), founded in 1995 and based in the US, is the accrediting body recognised by the US Department of Education for Montessori teacher-education programmes. It also accredits programmes affiliated with AMI, AMS, and other Montessori training organisations, not just one. A MACTE-accredited credential, regardless of which organisation issued it, is a reasonable quality baseline that doesn’t require picking a side in the AMI/AMS question.
Choosing between them, practically
- Want maximum international portability, and training from the organisation Montessori founded? AMI’s single global syllabus is designed for that.
- Want more flexibility in format, pace, or location, and are training for a specific country or school network? AMS’s TEP network tends to offer more options to fit around work or location constraints.
- Training for adolescent (12–18) work specifically? This is a smaller, less standardised field across both organisations. NAMTA’s work extending Montessori’s own sketched-out Erdkinder concept is particularly relevant here (see Cosmic Education: Curriculum Mapping and Understanding the Stages).
- Checking a credential you already hold or are considering? Confirm MACTE accreditation status directly rather than relying on branding alone.
Ongoing professional development
Training doesn’t end at the diploma. AMS requires continuing education to keep a credential active; NAMTA runs conferences and publishes ongoing material particularly relevant to elementary and adolescent practice; AMI and its affiliated training centres run refresher courses and international conferences. See Professional Development and Community for a fuller list.
Correction, 11 October 2026: an earlier version of this page said, in this site’s own voice, that AMI training offers the closest available fidelity to Montessori’s own original lectures and materials, and the closest fidelity to her original design. This site had not checked those claims. The page now gives AMI’s own description of its training, with a dated source. See the corrections log.
Sources consulted: AMI course documentation (montessori-ami.org; training pages last checked 11 October 2026); AMS Teacher Education Program documentation (amshq.org); MACTE, “History and Mission” (macte.org, 2024); American Montessori Society, Inc. v. Association Montessori Internationale, 155 U.S.P.Q. 591 (1967), for context on why no single organisation can claim sole ownership of the “Montessori” name itself.