Like many other mothers across the country, Caroline Cummons, a mother of two grown daughters, was keeping score.

"Yeah, I'm thinking about it," Cummons said yesterday while strolling past some mollusks at the Smithsonian's Museum of Natural History. "Your children should remember Mother's Day. If they don't, you think there is something wrong with them or else you failed to give them proper values. Yes, it is a big deal."

Cummons, visiting Washington from Yeadon, Pa., said one of her daughters comported herself well, sending her a card and a bathrobe. The other daughter, also in the museum looking at mollusks, managed only to say "Happy Mother's day."

"I said to Gail, that's the one who only half-remembered, 'Who do you think you are? Adopted?' " said Cummons. "What I am saying is probably going to embarrass Gail. But maybe she'll remember next year."

To avoid just that kind of guilt, Mother's Day was celebrated yesterday in metropolitan Washington in an orgy of thoughtfulness. Children served up countless breakfasts in bed. An inordinant number of women showed up in church with corsages. And there was a grid-lock of maternal affection on long-distance telephone lines. AT&T reported delays in handling an expected 20 million domestic and 1.2 million overseas calls.

Karl Klinger, a German engineer in Washington on business, got up at 6 a.m. yesterday to beat the long-distance crunch. He telephoned his mother in Iggingen, Germany, where it is also Mother's Day, spoke to her for 10 minutes and reported that she was "very pleased."

On what is often the busiest day of the year for the food-and-drink industry, area restaurants were packed with families. At Hogate's Seafood Restaurant on Maine Avenue SW, the crowd was "humongous" with diners waiting up to 90 minutes for a table, according to the management. "People wait because there is nothing else to do," said manager Art Forgette. "They are with their mothers all day long."

While most mothers spent a quiet day with their children, hundreds of others here and thousands across the country protested the nuclear arms race. Mothers, many of them with children in their arms, staged a demonstration in front of the White House. There were marches against nuclear weapons in Chicago, New Orleans, Topeka, Terre Haute and Des Moines.

The concerns of most families, however, remained more familial than global. Maureen Giller, for example, came home to see her mother in Alexandria.

"She won't let us forget what day it is. She's not that kind of mother," says Giller, a 21-year-old student at Westchester (Pa.) State College. "She drops subtle hints such as, 'If you ever want to give me a present, I could use a new tablecloth.' "

Giller says her mother is always in "a superior moral position" vis-a-vis Mother's Day. "She never forgets my birthday or any other special day."

The superior moral position of motherhood is something that Helen Costello banks on when assessing the chances of her four children remembering her "day of honor."

"I always remember them wherever they are in the United States, their birthday or whatever it was," said Costello, who was visiting Washinton yesterday from Morristown, N.J.

As of yesterday afternoon Costello's Mother's Day score card was incomplete: one daughter remembered, three sons yet to call in.

"I'm going home tonight," said Costello, "so I don't know who might call."

Ruth Richmond, a 64-year-old mother from Silver Spring, reported yesterday that, as usual, her two daughters had sent cards, but her three sons had done nothing. She was not pleased.

"It just hurts inside," said Richmond, who added that she never mentions Mother's Day to her sons. "If they can't do it of their free will I don't want it at all."