The mission of Marcellus Senior High School is to provide an education, which challenges, nurtures, and supports each student as a whole person.
The responsibility for this mission lies with the entire community includin students, staff, parents, and community members.It is our intent that each student will develop the responsibility, the confidence in his/her talents, and the knowledge necessary to function as a productive and contributing citizen in a diverse and challenging world.

Grades 9 through 12 are housed in the modern senior high school. The senior high opened in 1966 with additions added in 1971 and 1990. The latest addition contains a large group instruction room, a learning center, bookstore, art studio, music wing, and a 1000 seat auditorium. An extensive extra-curricular program is also available in order to provide for the fullest development of each individual student. The campus is fully wired with fiber optic cable and students have access to a wide variety of technology applications. Distance learning is also in place through satellite connection. Approximately 90% of all graduates go on to post-secondary education.