See page 408 for a 1950's photo of a First Communion procession in St. Margaret Mary church. Parents and Sisters of Mercy may be seen at the procession. See page 472 for establishment of the parish in 1923. Page 473 has an exterior photo of the church. See page 606 for a reference to parishioners from Ghana. The rectory address is 1914 Morris Ave., Bronx NY 10453, telephone 718-299-4233. The parish website is linked here.
The parish school address is 121 East 177 Street, Bronx NY 10453, likewise between Morris Avenue and the Grand Concourse. The telephone number is 718-731-5905. With an enrollment somewhere over 300, it would seem that this school has one or two sections per grade.