The Iona School underwent significant transformation in the mid-1950s. In order to create a more focused education for elementary and secondary students, The Iona School was split into Iona Preparatory School and Iona Grammar School in 1954. In February 1955, Iona Grammar School, serving pre-kindergarten through eighth grade students, relocated to its present campus on Stratton Road, the former home and estate of Harry M. Stevens, a food concessionaire who is sometimes attributed with the invention of the hot dog. For the next six decades, Iona Grammar and Iona Prep (as a high school) would evolve as distinct academic and financial entities, though each remained as a Christian Brothers school.