I attended Saint Mary Magdalen school on Concord Pike for all my grade school years (K-8) starting in 1976. There have been many improvements with the school and parish and I think it is probably one strongest parishes in Wilmington. There is only 2 other catholic grade schools in north Wilmington (19803 and 19810 area) which are IHM this school is part of the diocese as well and there is also St Edmond's Academy which is a private all boys school. Archmere Academy is a private catholic high school in Claymont. Here is a link to the schools of the Catholic Dicoese of Wilmington if you looking for just catholic schools: http://www.cdow.org/schools.html. There are many private schools in this area depending on what age group and if you are looking for any particular program. As I mentioned above I went through Catholic school and high school my whole life, even college, so if you have any questions about Catholic education or any of the Catholic schools in general please do not hesitate to contact me.
Here is a link to the listings of private and catholic schools by zip code.
Best of luck in finding the perfect school fit.........................chris