The SAS student body is made up of over 65 nationalities, with over half of the students being United States citizens. Singaporean student numbers are limited as Singapore government regulations prevent most local students from attending international schools within the country. The majority of the teachers come from the US, and staff members from twenty other countries also work at SAS. Most are hired overseas, and over 80% hold master's degrees. The maximum number of students per class in preschool and pre-kindergarten is 16, while for kindergarten through grade 12 it is 22.