Harvard Student Agencies (HSA) Tutoring is a tutoring, test prep, and college prep service company run by Harvard students, connecting top Harvard student tutors with K-12 students in need of mentorship, tutoring, and educational assistance. HSA Tutoring is different because the tutors are current students who’ve recently been through and excelled at the very classes, subjects, and tests they’re tutoring, so they have a recent, up-to-date, and intimate knowledge of the material and how best to efficiently master it.