Most teachers don't choose a curriculum. The curriculum chooses them. You take a job at the school that hired you, and suddenly you're an IB teacher or a Cambridge teacher by accident rather than by design. But if you're planning your international career strategically, the choice of which curriculum to develop expertise in matters more than most job guides will tell you.
The three dominant frameworks in international schools are the International Baccalaureate (IB), Cambridge International Education (CIE), and the College Board's Advanced Placement (AP). Each one has a different footprint globally, different requirements for teachers, and different implications for where your career can go. Here's what actually separates them from a hiring perspective.
The Numbers: How Big Is Each Curriculum's Market?
This is the part teachers rarely look up, and it should come first. The size of each curriculum's market tells you how many schools you're potentially eligible to apply to.
Cambridge runs programmes in over 10,000 schools across 160 countries [2]. It's the largest footprint of the three by a significant margin. The IB operates in nearly 6,000 schools worldwide, with the Diploma Programme (DP) offered at over 3,880 of those across 157 countries [3]. Between 2020 and 2024, the number of IB programmes offered worldwide grew by 34.2%, which reflects a genuine expansion in demand for qualified IB teachers [3]. AP sits further behind internationally. It's strong in the United States and recognized by virtually every American university, but outside North America, very few countries accept AP credits for university admission [1].
What this means practically: Cambridge gives you the largest pool of potential employers globally. IB gives you a smaller but rapidly growing pool with a strong premium attached to the credential. AP largely confines your career to American-curriculum schools, which exist internationally but represent a narrower market than either of the other two.
What Each Curriculum Actually Requires of Teachers
International Baccalaureate
IB has the most rigorous teacher authorization process of the three. For a school to become an IB World School, it must go through a formal candidacy and authorization process that includes sending teachers to mandatory IB Category 1 workshops [4]. Every DP subject teacher must attend a Category 1 workshop in their subject before the school can achieve authorization. Theory of Knowledge teachers, CAS coordinators, and Extended Essay coordinators each have their own required workshops [4].
As of 2025, the IBO updated requirements so that schools applying for candidacy on or after July 1, 2025 must have their Extended Essay coordinator attend a Category 1 workshop, and language and cultural studies teachers have a similar new requirement for applications submitted after November 2025 [4]. These updates reflect the IB's ongoing push to standardize professional development.
The practical implication: IB workshops cost money and take time. Schools absorb some of these costs, but the process signals genuine commitment from the school to the programme. Teachers who've completed Category 1 workshops hold a credential that transfers across any IB World School globally.
The IBO also offers IB Educator Certificates (IBEC), which are formal professional qualifications in IB pedagogy. These aren't required to teach, but they add weight to a CV [4].
Cambridge International
Cambridge doesn't require teachers to hold a specific Cambridge certification to teach IGCSE or A-Level subjects. Subject knowledge and a teaching qualification from your home country are generally sufficient. Cambridge does offer the Cambridge International Diploma in Teaching and Learning (CIDTL), a portfolio-based qualification assessed by Cambridge Assessment International Education, but it's optional rather than mandatory [5].
This lower barrier to entry is a double-edged thing. It means Cambridge schools are easier to get into without prior curriculum-specific training, which is good for teachers building an international career from scratch. But it also means Cambridge experience alone carries less credential weight on a CV compared to documented IB workshop training.
Advanced Placement
AP doesn't certify teachers at all. College Board requires schools to submit an AP Course Audit to authorize each AP course, but that's an institutional process rather than a teacher credential [6]. The expectation is that AP teachers hold standard subject-area qualifications and have at least three years of classroom experience before leading an AP course. The exception is AP Capstone, which requires a four-day AP Summer Institute before teaching [6].
This means AP adds very little to a teacher's portable credential set. You can say you've taught AP Biology or AP Calculus, but there's no external verification or certification that travels with you the way an IB workshop certificate does.
Which Curriculum Opens More Doors Internationally?
The honest answer is that it depends where you want to work.
If your goal is the Middle East (UAE, Saudi Arabia, Qatar), Southeast Asia (Singapore, Thailand, Malaysia), or top-tier schools in Asia generally, IB and Cambridge are both strong. IB schools tend to cluster in cities with large expatriate populations and premium school markets. In China, international schools run primarily on Cambridge A-levels (roughly 45% of curriculum offering), followed by AP (around 30%), with IB accounting for about 23% [7]. So for a career in China specifically, Cambridge and AP experience are more useful than IB alone.
Singapore runs all three curricula across its international school sector. Dubai similarly hosts IB, Cambridge, and American-curriculum schools in significant numbers. Bangkok skews toward IB and Cambridge for its higher-end international schools.
If you're aiming specifically at American-curriculum schools, AP experience matters. These schools exist in most major international cities, typically serving American expat communities. But they're a narrower market than the combined IB and Cambridge ecosystem.
The genuine career risk with AP specialization is geographic lock-in. Teachers who build careers primarily around AP tend to find it harder to pivot to non-American-system schools later, partly because AP subject expertise doesn't map cleanly to Cambridge or IB syllabi, and partly because hiring committees at Cambridge or IB schools don't weight AP experience heavily.
Career Trajectory: Where Each Path Leads
IB training compounds over time in ways that Cambridge and AP don't. The workshop framework, the portfolio of PD, the documented engagement with IB pedagogy: all of it builds a CV that signals serious commitment to a specific and growing educational philosophy. Schools actively recruiting IB teachers ask for prior IB experience in their vacancies as a near-universal condition [7]. That makes entering the IB market harder initially, but once you're in, the market is loyal to experienced IB teachers.
Cambridge schools are more flexible about hiring teachers without prior Cambridge experience, which makes it a better entry point for teachers new to international education. The tradeoff is that Cambridge experience, while widely applicable, doesn't carry the same credential premium that IB workshop certifications do.
AP experience works well as a supplementary credential alongside IB or Cambridge, particularly for American or Canadian teachers whose subject qualifications already align with US standards. As a standalone career path in international schools, it's limiting.
A Practical Note on Getting IB Experience
The biggest catch with IB is the "you need experience to get experience" problem. IB schools prefer teachers with IB backgrounds, but if you haven't taught in an IB school, you don't have one [7]. The practical workarounds are: take IB workshops independently (the IBO offers some paid workshops open to individual teachers), apply to IB candidate schools that are in the authorization process and therefore actively onboarding teachers into IB training, or start at a Cambridge school and cross-train if the school offers both programmes.
It's not a fast process. But IB training is arguably the most transferable curriculum credential in international education right now, given the programme's continued global growth.
