Sigtunaskolan Humanistiska Läroverket (SSHL) is a coeducational independent school for boarding and day students between the ninth and twelfth grades.

Dating back to the mid-1920s, there were two boarding schools in Sigtuna: Sigtunastiftelsens Humanistiska Läroverk, which was founded by Bishop Manfred Björkquist, and Sigtunaskolan, the other boarding school that was founded by theologian Harry Cullberg.

The school offer a variety of subjects to cater to the diverse body of students taking the program at SSHL and offer support CAS (Creativity, activity, service), a central emphasis of the IB program by organizing service trips to Laos, Nepal and Kenya.

SSHL is a member of Sweden's Boarding and Private Schools' Sports Organization (Svenska Internat och Privatskolors Idrottsorganisation, SIPSI), founded in 1983,[6] which allow students from different European and Swedish schools to compete in various sporting events throughout the academic year.

Students are able to represent one of the school's "Houses" to which they belong, and take part in different athletic tournaments.