School generally commences on or before August 13th of each year. New student/parent orientation for MS and HS are scheduled the day before school opens. School usually ends after the first week in June of each year. You will find that the ISB calendar consists of the same number of instructional days as US schools. Please check the ISB Calendar for the most up-to-date information.

Classes at ISB begin early and end early in order to beat the Bangkok traffic. Classes in the Elementary School begin at 7:35am and end at 2:20pm. Classes in Middle School and High School begin at 7:20am and end at 2:25pm. After-School activities in Elementary School and Middle School generally run from 2:35 – 3:35pm.

Montri Transportation Company has been providing transportation services to ISB since 1976. Montri will provide transportation services for students up to 50 kilometers away. Each bus is air-conditioned, has retractable seat belts, and a bus supervisor. Service is door-to-door for all students before school and immediately after school at 2:20pm. There is an Elementary after-school activity bus at 3:50pm which also offers door-to-door service for students in grades Kg – 5. Middle School and High School students also have additional 3:50pm and 5:10pm bus services that travel on the main routes. Students will be dropped off on a main route at a point closest to their home. For many students, this means a short walk into a Soi (lane).

The ISB class maximum class sizes are as follows:

  • KG 17 students; Grades 1-2, 20 students; Grade 3, 21 students; Grades 4-5, 22 students
  • The average Middle School class size is 17 students
  • The average High School class size is 15 students

ISB has uniforms for sale at the ISB Book Store on our campus. The uniform consists of a polo shirt with the school emblem with either khaki or black shorts, pants, or skirt. Physical Education (PE) uniforms are required at all levels. This is a unisex uniform that consists of black knit shorts and a gray ISB T-shirt. Elementary School students wear the PE uniforms to school on the day they have PE classes. Middle School and High School students change into their PE uniforms before PE class in the locker rooms provided.

Our Middle School/High School (main) cafeteria is open from 7am – 5pm. This cafeteria sells breakfast, snacks, and hot lunches. The main cafeteria also has a cold kitchen that offers salads, sandwiches, and fresh fruit. Meals in the main cafeteria are à la carte and can be purchased with cash or ISB ID cards can be used as Smart cards to make cafeteria purchases. The Elementary School has their own cafeteria for Grades Kg – 5 which offers a choice of Asian and Western entrées, Chinese noodle soup, or sandwiches each day. There is also a fresh fruit and salad bar. Lunch and snacks in the Elementary School cafeteria are included in tuition.

Once their children have been admitted to ISB, parents will be issued and ISB ID. This ID will allow parents to use the libraries and sports facilities, such as the tennis courts, weight room, and track, at ISB.

A great deal of effort is invested in creating balanced classrooms in order to provide for the most effective instruction. We try to balance each Elementary School and Middle School classroom in terms of gender, nationality, language proficiency, academic ability, and maturity level. Parents may complete a class placement form, available in the Elementary School counseling center, if they wish to have a voice in the class placement process.

If you would like to be put in touch with a parent at our school via e-mail, please send an e-mail to the ISB Admissions Office at and they will forward your e-mail to an ISB parent. Please include your home country, the age of your child(ren), and any other relevant information about you and your family in the e-mail so that an appropriate match can be found.