A new campus was constructed at 865 South Ronald Reagan Boulevard in 1969. The original campus became R. T. Milwee Junior High School, named after Rayburn T. Milwee, Sr., who taught at Lyman from 1939 to 1949, served as principal from 1949 to 1952, and served as Superintendent of Seminole County Schools from 1952 to 1967. In 1970, Seminole County transitioned from the junior high school system to the middle school system, causing Lyman High School to now accommodate 9th grade in addition to 10th, 11th, and 12th grades. During the transition period from 1970 to 1971, the school mandated "double sessions," in which half of the school would attend from 7:00 am to 1:30 pm and the other half would attend from 11:30 am to 6:00 pm.

In June of 1971, the Milwee Middle school, where Lyman's original campus was, closed and reopened as a satellite campus for Lyman High School during the 1971-1972 school year. For the 1972-1973 academic year, all Lyman students returned to the primary campus and the satellite campus was used for Lake Brantley High School instead. In 2000, Lyman established the Institute for Engineering, a magnet program emphasizing mathematics and science.]]>
Lyman High School 1965-1966 school year]]> The Greyhound Staff of 1966: The Greyhound 1966, item 373.105 LYM 1966, (Longwood, FL: Lyman High School, 1966): Seminole County Public Schools Collection, UCF Public History Center, Sanford, Florida.]]> The Greyhound Staff of 1966]]> The Greyhound Staff of 1966.]]> The Greyhound Staff of 1966: The Greyhound 1966, item 373.105 LYM 1966, (Longwood, FL: Lyman High School, 1966).]]> The Greyhound 1966, item 373.105 LYM 1966, (Longwood, FL: Lyman High School, 1966).]]> UCF Public History Center, Sanford, Florida.]]> Seminole County Public Schools Collection, Student Museum and UCF Public History Center Collection, Sanford Collection, Seminole County Collection, RICHES of Central Florida.]]> The Greyhound 1966, item 373.105 LYM 1966, (Longwood, FL: Lyman High School, 1966), page 130.]]> Lyman High School.]]> Lyman High School and is provided here by RICHES of Central Florida for educational purposes only.]]>