When Rosemary Ringe first came in 1948 to teach second grade at Blessed Sacrament School near Chevy Chase Circle, the classrooms were teeming with 55 and 56 children each. Discipline was tight. She was the only lay teacher in a school dominated by nuns.

Now, 36 years later, at age 63, Rosemary Ringe is retiring. She leaves a school where class size has been halved, discipline has loosened and the nuns have largely vanished -- a common experience at most of America's Catholic schools in the last four decades.

She has lived through tumultuous changes in education, religion and the church itself. But in the balance -- and there are notable exceptions, she said -- the changes have been "basically for the good."

Her 7-year-old second graders are "less disciplined and . . . have a shorter attention span," much of it attributable to television, Ringe said. On the other hand, she said, "the kids seem brighter today . . . . They are more sophisticated at an early age."

The one constant over the years, she said, is that "they want to please, and they want to learn."

Another constant at Blessed Sacrament has been Rosemary Ringe herself, a diminutive and gentle woman, an ex-nun who quit her order after seven years in the 1940s when such action was neither common nor fashionable. She joined the Blessed Sacrament teaching staff after leaving the order, married attorney Fred Ringe in 1952 and, except for five years in the 1950s spent helping to raise their adopted son, Paul, has taught continuously at Blessed Sacrament since 1948.

She scoffs at talk of the decades-long continuity she has provided Blessed Sacrament. For most of her years at the 410-pupil elementary school at 5841 Chevy Chase Pkwy. NW, she has taught second graders, including the children of children she taught a generation ago.

"She is the most caring and loving of people," said school secretary Peggy Collins, herself a veteran of almost 24 years at Blessed Sacrament. " . . . The children are always her first concern."

"She has an open and loving stance with the children," said school Principal Sr. Rose Cecelia, of the Sisters of the Holy Cross.

". . . She'll hug them, she'll kiss them, and her affection gives them a sense of security."

Professionally, said Sr. Rose, "she knows the 7-year-old. She has a wisdom about them, . . . an uncanny insight into the strenghths of an individual child."

For Rosemary Ringe, three major changes over the years have left an indelible mark on Catholic education: television, smaller classes and the reforms of Vatican II.

With the advent of TV in the late 1940s and early 1950s, she said in a recent interview at her home in Silver Spring, children seemed to develop a shorter attention span. "You had to change your approach to teaching ," she said. "You have to put more into it. You have to be entertaining and figure out more things to do."

While discipline seems to have declined, she said, the result has been mixed. "The kids are not afraid of you at all, the way they used to be ," she said. " . . . Today, they treat you like a mother. They call you 'Mom' sometimes . . . . They come up and hug you."

Also during the last 35 years, Catholic families have become smaller, resulting in smaller classes. "The smaller classes work to the children's advantage," she said. "They get more attention -- and they demand it."

Perhaps most important, she said, are the Vatican II reforms that have brought the Mass closer to participants and made the mysteries of the sacrament of communion less fearful to children.

As a teacher, Ringe has prepared hundreds of second graders for their first communion. "Now we let them see and feel the unconsecrated host wafers beforehand, so the experience is not frightening," she said. In the same way, children in the past often had difficulty swallowing the wafer when it was placed on their tongues by a priest, but today with the Vatican II option of taking the host first in the hand, "it is a more relaxing experience for the children," she said.

In addition, she said, "children participate more now in the Mass . They do the readings and the Prayer of the Faithful and bring up the offertory . . . . It involves them more, so they understand it better."

Another church reform, permitting women a greater role in the Mass and other church functions, "is great," Ringe said. "Why not? We're human." Asked if she thinks there may someday be a woman pope, she said, decisively, "No, not in my lifetime. We don't even have any lady priests, and look how long it's taken to come this far."

Ringe will retire at the end of the current school year, although she said she would like to continue. Plagued with developing cataracts, she said she may have to undergo eye surgery and a lengthy recovery later this year that would interrupt her teaching schedule.

In retirement, she said, she plans to travel with her husband and "look up some of my Irish family roots."