The idea of having a Lutheran high school first surfaced in a report by Prof. E. Younghans (who was then the principal of Immanuel Christian Day School) given in May of 1949 to representatives of Baltimore city congregations. A permanent committee of 12 was selected to study the possibility of a Lutheran high school.
In the summer of 1958, the property was purchased and after several years of study and preparations, the groundbreaking ceremony was held on September 27, 1964, with the completion date set for August 15, 1965, with classes starting in September for grades seven, eight, and nine. The present-day upper school building was opened and dedicated on August 29, 1965.
In 1968, a second building (the present middle school building) was dedicated and the first class of 30 students graduated on June 11, 1969. In 1974, due to continued growth, the school undertook a fundraising campaign and built the Lutheran Activity Center, which was completed by the start of school in 1974. In September of 1987, the Bridges Media Center was finished and dedicated.
Over the years, Baltimore Lutheran and now Concordia Prep has continued to grow and prosper through the dedication and financial support of the Baltimore Lutheran High School Association and support of Association Churches.