The Singapore American School (SAS) is a non-profit private international school in Singapore. Established in 1956, the school offers an American-based curriculum from preschool through to Grade 12 for 3,700 expatriate students, making it the largest international school in the world. Approximately two-thirds of the students at SAS are US citizens, with the rest of the student body comprising more than 50 different nationalities. Few Singaporean students attend the school as Singapore government regulations prevent most local students from attending international schools within the country.