SIS Swiss International School Schönenwerd is a private bilingual day school in Schönenwerd, canton Solothurn, between Aarau and Olten. It takes children from age five to the end of primary school: a kindergarten for ages five to six, then primary school from age six. German and English are both languages of instruction throughout. Around 90 students attend, from 20 nationalities. It is the group's only campus in Solothurn and one of seven in Switzerland.