SSIS, originally Stonyhurst School, (lacking the later mentioned international title given) was founded in 1996 offering only a pre-school program and practicing in an English speaking environment.

Aside from the academic subjects – Math, Science, English, Social Studies, Languages, there are also courses on Arts, Culture and Sports - Physical Education, Values Education, Home Economics, Technology, Robotics, Financial Literacy, Football and Interest Clubs.

Aside from the courses in Mathematics, English, Science, Social Living and Global Education, Filipino, Home Economics and Technological Arts, Computer/Robotics, Music, Arts, Physical Education and Foreign Language (which are also offered in the Grade School Department), the High School Department also offers courses on Economics, Accounting, Investment Management & Entrepreneurship and Financial Literacy.

Senior High School (SHS) covers the last two years of the K-12 Program in accordance to the Republic Act No.

Specialised Subjects that are included under this strand are Chemistry 1 & 2, Biology 1&2, Practical Research, Pre-Calculus, Calculus, Business Math, Physics 1 & 2.

This strand focuses on University and College courses such as Accountancy, Entrepreneurship, Business Management, Marketing and the like.