The Internet School of Orthodox Studies Fall 2001 series of 90 minute educational classes are intended to assist Orthodox Christians to more fully understand the catechetical content of their Orthodox liturgical heritage. The classes will also assist religious educators to integrate liturgical theology within their respective classroom curricula. This series is presented by Rev. Dr. 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 These classes have all been archived on the goarch.org website with the assistance of the Archdiocese Department of Internet Ministries.