In 1973, Mrs. Christy approached St. Chrysostom’s Church Rector Bob Howells and Senior Warden Bill Leff about starting a parish-based pre-school for parish and neighborhood families. With a modest Vestry (the Church's Board) contribution and a community member’s generous donation, St. Chrysostom’s secured appropriate licenses from the City of Chicago Department of Buildings and the State of Illinois Department of Children and Family Services. In September 1974, the Day School, led by Mrs. Christy as its Founder and Headmistress, opened its doors as a half-day program with three staff members and 27 students. Since that time, the Day School has operated as an unincorporated parish day school that is wholly owned by the Church and governed under canon law by the Vestry and the Rector. The Day School’s advisory board is a committee of the Vestry of St. Chrysostom’s reporting to the Wardens and the Vestry and serve at the pleasure of the Vestry. The Rector retains the ultimate authority for the Day School including the responsibility for hiring Mrs. Christy’s successor.

As of the 2016-2017 school year, the Day School has 155 students enrolled in six programs for children aged from 22 months to 5 years serviced by a team of 20 teachers, assistants and administrators. As one of the only Episcopal preschools in all of Chicagoland, the Day School has earned a reputation for offering extraordinary teacher attention to students, for its emphasis on forming the whole child, for nurturing genuine friendships among parents and families, and for its service to the wider community. Over the 43 years of Mrs. Christy’s leadership, the Day School has made a difference in the lives of more than 6,100 children enrolled in the Day School’s programs from 1974 through 2017 and continues to evolve to meet the needs of the community including the recent addition of extended day programs for the morning fours, junior kindergarten and preschool classes.