The Upper School implements its program under the aegis of the School’s Mission Statement. In 1997–98, the Upper School Faculty endorsed the following philosophy as describing the key elements underlying an OES Upper School education.

The Upper School experience at OES is designed to create lifelong learners who take responsibility for their own education. Graduates of OES are expected to think critically, express themselves with clarity and confidence, and behave respectfully and responsibly.

The atmosphere at OES is academically demanding with high ethical standards.

To aid their growth as scholars and as citizens, our students are given a balance of support and autonomy to help them confront and meet the high standards of the school. Students are encouraged to attempt many areas of learning and activity to discover their gifts and interests, but they are also encouraged to make choices about their priorities. Our students are treated with respect and acknowledgment of their growing maturity.

The faculty is passionately committed to their students and to their respective fields of study. Students and faculty alike value intellectual freedom, and the Anglican tradition of our school demands that we value public debate about intellectual, ethical, and spiritual matters.

Faculty and students regard our community life very highly, and all make a commitment to that life, as well as to the larger community.