The Internet School of Orthodox Studies Spring 1999 series of 90-minute educational classes are intended to assist Orthodox Christians to more fully prepare themselves for the celebration of Lent and Easter. Participants will examine the Scriptural, Liturgical, and theological aspects of the Hymnology of Great Lent in a casual yet systematic fashion. This series is presented by Rev. Fr. Frank Marangos.

Established by the Department of Religious Education in 1998, ISOS ran through the Fall of 2005 as a means to assist Orthodox Christians to better understand the teachings of the Orthodox Church. These classes have all been archived on the website with the assistance of the Archdiocese Department of Internet Ministries.