I assume you're talking about St. Joseph elementary school on 115 Telford Street in East Orange. I don't know the name of the principal off the top of my head, but you can contact the school directly at (973) 674-2326 or you can call the Archdiocese of Newark, Vicariate of Education at (973) 497-4260.
Jacobus "Jack" Vollenberg
RE Appraiser/RE Sales Associate
Vollenberg Appraisers/ERA Statewide Realty