The closings are part of a Long Island-wide and nationwide trend. According to Sean Dolan, a spokesman for the diocese, enrollment in its grammar schools has dropped 34 percent in the past decade — from 28,709 during the 2000-01 school year to 19,261 in 2010-11. According to Diocese of Rockville Centre Education Department enrollment reports, the number of students in Catholic schools in Nassau and Suffolk counties dropped by 4,000 from 2004 to 2010.

In June, the Blessed Sacrament School in Valley Stream closed, and in 1994, the St. Vincent de Paul and St. Boniface schools in Elmont closed.

Dolan said he believes that several factors are responsible for the declining enrollment on Long Island — which, he said, is a problem for public schools, too. One likely catalyst, he said, is changing demographics. He explained that the number of young parents with school-aged children who are staying on or moving to Long Island has dropped over the past decade, adding that according to diocesan officials, Long Island’s grammar-school-age population is predicted to drop 7.5 percent by 2015.

Higher school and property taxes, as well as increasing tuition rates at Catholic schools, have contributed to the declining enrollment trend, Dolan said. In 2007-08, annual tuition for an in-parish student at the Sacred Heart School in North Merrick St. Catherine of Sienna was $4,050; for 2011-12, it’s $4,892. Rates are even higher for out-of-parish students.

“Public schools on Long Island are generally good, so if you’re a parent and paying a lot of taxes, you might decide to put your child in a public school,” he said.

Lynbrook’s Our Lady of Peach School Principal Sis. Mary Dowden said, “I feel exhilarated that we are able to stay open, but at the same time, terribly sorry for the schools who are closing, the administrators, teachers, students and families. If some students choose to come over here, I would be very happy to have them.” Officials at St. Raymond’s School in East Rockaway declined to comment for this story.

Further causes for enrollment decline are a general shift in dedication to the Catholic Church — in addition to school enrollment, Mass attendance has gradually declined — and a lack of tax credits or other governmental financial help for Catholic schools, Dolan said. “There is also no recognition by the government of the value that Catholic education brings to society,” he said.