Saint Peter School opened in 1962 as an addition to The Church of St. Peter Parish with eight classrooms and 236 students. With enrollment increasing steadily, an expansion of facilities was necessitated. In 1966, the school was enlarged to sixteen classrooms, a multi-purpose room, a library, a staff room, and custodial facilities. The school continued to thrive under the leadership of Father Joseph Step, pastor from 1966-1986.
In 1985, Sister Annamae Murphy, principal of Saint Peter School from 1983 to 1989, approached Father Step about the possibility of a kindergarten. Father Step and Sister Annamae collaborated with the Parish Finance Board to build the Father Step classroom addition, which included two kindergarten rooms, a music room, computer lab, faculty lounge, two lavatories, a conference room, and offices for the principal and secretary. Saint Peter School opened the 1986 school year with two full-day kindergartens and classrooms in grades kindergarten through grade four full to capacity.
Father Joseph C. Step retired as pastor in October 1986 and was replaced as pastor by Reverend Kenneth J. Wolnowski.
It became evident with the growing enrollment in the kindergarten classes that a preschool was also needed to accommodate the needs of the parents. In 1994, Father Wolnowski, Principal Sister Laurie Divoky, and the Parish Finance Board initiated plans for a preschool. Saint Peter Preschool opened for four- and five-year-olds in September 1994. A three-year-old program began in September 1996. Initially, the preschool was located at Lorain Catholic High School for many years, but with the renovation of the parish facilities in 1999, the preschool moved to the East Wing of the parish rectory.