California Prep International School.

Which direction it is from Ayutthaya

Ayutthaya’s defining schooling problem is not distance, it is direction. Guides written from Bangkok outwards assume the only road out is south. It is not.

EAST and slightly north, on Mittraphap (Friendship) Road in Kaeng Khoi -- the Bangkok-Korat trunk route. Further from Ayutthaya than SJMIS and on a different road, so the two are not interchangeable despite both being "Saraburi".

Where this school stops

Grade 12, around age 18.

What a leaver actually holds

The curriculum label and the leaving qualification are different things. For a family that may move country again, this line is the decision — and a blank cell is itself a finding.

The school describes a K-12 American programme on the California curriculum and publishes graduating cohorts by school year. It does not name an external examination board or an accredited diploma-awarding body on its public pages, so what a leaver holds -- and who stands behind it -- is a question to put to the school in writing before enrolling. A blank here is a finding, not an omission in our research.

Where the campus actually is

9 Moo 11, Tambon Ban Pa, Amphoe Kaeng Khoi, Saraburi 18110

Mittraphap Road at Ban Pa, Kaeng Khoi. This is the main highway to the northeast; traffic behaves differently on it from the Phahonyothin corridor. Drive it at 07:00 before deciding.

Ayutthaya area guides families use for this school run: Wang Noi & the Industrial Corridor

The curriculum pathway, stage by stage

• Kindergarten.
• Elementary.
• Middle School.
• High School, to Grade 12.
• Throughout: the school's own framing is learning "on CPIS Campus and in the comfort of your home" -- the blended element is not an add-on, it is the model.

Accreditations, authorisations & affiliations

Three different claims, routinely collapsed into one. A whole-school accreditation (WASC, CIS, NEASC, Cognia) assesses the school itself. An examination-board authorisation (College Board, Cambridge, IB) means it may enter pupils for those exams. A membership or affiliation is neither. And “none named” is a fourth state, distinct from “not accredited”.

• NONE NAMED. The school's own public pages do not name a whole-school accrediting body. This is the third state of the accreditation question -- distinct from "not accredited" and from "we could not find one" -- and it matters more here than usual because the delivery model is partly online.
• Note carefully: the founders' published biographies list extensive WASC and CIS accreditation CONSULTING for other schools across Thailand and the region. Consulting experience belongs to the individuals, not to this school, and must not be read as an accreditation held by CPIS.

Religious character

Present, but not labelled on the front of the school. The published mission ends with "character development with positive attitude and love to mankind and the Most Powerful Spirit or Creator God", and the school's own news archive records an annual Meditation and Week of Prayer. Both founders have long careers in Seventh-day Adventist education. The school does not brand itself as a faith school and publishes no statement of faith we could find, so a family for whom this matters in either direction should ask directly rather than infer.

Boarding

For an Ayutthaya family this is not a lifestyle question, it is the question. Without boarding or a van route, a Saraburi school is a daily drive across a provincial boundary.

Reported as available by the independent censuses. The school's own public pages do not carry a boarding section, so confirm the arrangement, the supervision and the location directly.

Who it suits

Families who actively want a blended model -- and, unusually, that describes a real slice of BAANLYY's audience. A DTV or remote-work family that travels, or one living out along the Mittraphap corridor, may find a school built around part-home study fits better than one that penalises absence. Families who want a conventional full-time campus school should read the delivery model carefully first.

What we could not verify — and where sources disagree

We publish these openly rather than smoothing them over. A school guide that hides its uncertainty is not much use to a family making a decision this big.

• Co-founded 14 November 2010 by Dr Phakdee Mangmiwatthana and Dr Adelino T. Libato, and licensed in 2011 -- both dates published on the school's own site.
• THE FEE FIGURES DISAGREE. The two independent censuses currently quote different 2025/26 ranges for this school -- one 72,000-95,000 THB, the other 84,000-107,000 THB. Neither is the school's own published schedule. This is exactly why BAANLYY publishes no per-school fees: ask the school.
• The school runs two domains. The website is caprepschool.com; the published email addresses are on caprepschool.net; and one of the admissions links on the homepage is labelled with the .net address while the underlying mailto points at .com. Use the phone number to confirm which mailbox is actually monitored.
• The blended model is the school's stated identity, not a pandemic leftover -- one census describes it as among the first complete e-learning international schools in Thailand. That is a legitimate model and some families want it. It is also the fourth city in this rotation where post-16 study turns out to be partly remote, after Pattaya, Koh Samui and Krabi, and the pattern is now strong enough that it should be checked everywhere.
• A founder biography published on the school's own site lists "Khon Kaen International School, Kaeng Khoi, Saraburi". Khon Kaen and Kaeng Khoi are different provinces several hundred kilometres apart, so at least one element of that line is wrong on the school's own page. Minor in itself, but a reminder to verify rather than transcribe.
• The 2026-2027 school year is published as starting 10 August 2026, which is the conventional Thai international-school calendar. Worth confirming against your child's current school year to avoid losing or repeating a term.

Ask every school in the Ayutthaya catchment this

• Before you accept a Bangkok commute, price the eastern option. Saraburi has four international schools at a broadly comparable radius from Ayutthaya, three of which board, at published fees in the low hundreds of thousands rather than Bangkok's four hundred thousand to over a million. Every guide sends you south; check east before you sign a lease.
• Ask Saint John Mary for the current school van route list, in writing. Whether a route reaches the Wang Noi or Bang Pa-in side of Ayutthaya is the single fact that decides whether the strongest international school within reach is a day school or a boarding school for you.
• When a school says boarding, ask whether it means a dormitory on campus or a homestay placement with a partner family. They are different products with different supervision, and directories record both as "boarding: yes".
• Ask what qualification a leaver actually holds, and who awards it. Three of the four Saraburi schools run American programmes and only one of them also hosts the College Board, SAT and TOEFL testing on site. One names no leaving qualification at all.
• Ask whether the final years are taught on campus or partly online. One of the four is built around blended learning by design and says so; that is a feature for some families and a deal-breaker for others.
• For any Thai school's English Program, ask how many periods a week are genuinely delivered in English, and what a non-Thai-speaking child faces at admission. Cost is not access: Thai EP and state-school entry usually runs through an examination sat in Thai on a fixed national timetable.
• Before shortlisting any school you found in an English-language listicle, apply the four-part existence test: does it have its own domain, a findable street address, a phone that answers, and does its own homepage carry any closure or rebranding notice? The most syndicated page on Ayutthaya schooling currently recommends a school that does not exist.

Sources & References

• Ministry of Education, Thailand

Primary and official sources are cited above. Government rules, fees and procedures in Thailand change over time and vary by office; always confirm current requirements with the relevant authority before relying on them. BAANLYY never takes paid placement in editorial content.