THE NEWS ITEMS hit with unique, chilling force, and they stay with you, these terrible stories of what adults do to children, and every so often the incident is so awful that it propels into law a piece of child abuse legislation that has been languishing in a human resources committee. Then the community and the lawmakers settle back to business as usual until the next kid gets thrown off a bridge by an adult.

Some of the incidents we've been reading about lately are peculiarly savage -- incidents in which parents are accused of trying to exorcise demons from their children by beating them with Bibles and throwing them out of windows, or the father who places his child on the highway so it can be run over. And while we may never forget the picture of the horrified father whose child was baked and scalded in New York last week, these kinds of incidents are too crazy and mercifully too rare to tell us much about child abuse.

Far more common are the cases in which the parents simply get frustrated and fed up and resort to extreme physical punishment in an effort to get the child to behave. And despite all the new reporting techniques, the increased public awareness of child abuse, the cooperation between hospitals, police and welfare agencies, these are the cases that have persisted, year after year, with no significant decline. Federal studies indicate that one million cases are reported a year, and perhaps another 2 million cases of child abuse occur each year but are never discovered.

These are the cases that cut across lines of race, sex and economics. These are the cases that have as a common bond the simple and sometimes deadly fact that the parents can't cope. We cringe at the stories of parents hitting their children in the head or throwing them down the staircase. We are revolted at the cruelty and the stupidity. But those among us who have paced the floor all night with a frantically screaming infant or who have tried to be patient with an intractable toddler can at least understand the scenario for violence against children.

Dr. Brian Blackbourne of the D.C. Medical Examiners Office has studied the 35 fatal child abuse cases that have occurred in Washington since 1972. "In many of the cases," he says, "it is a building up of minor frustrations. A child that just keeps crying, that causes the parent or parent substitute to lose control of themselves and lash out at the child. These people are often immature and don't handle their emotions that well. And the loss of the extended family, where you don't have the grandmothers to come in an help out is another factor. Where there's no one helping out, that just adds to the building up of frustrations, and if you've got domestic or economic problems as well, the whole thing sort of adds up."

Washington, largely because of efforts by people at Children's Hospital and a few officials in the Corporation Counsel's Office and the Human Resources Department, has been in the forefront of efforts to prevent child abuse by identifying children in risky situations and trying to care for them in whatever ways seem most appropriate.

Part of the problem, of course, is no one knows for sure when it is wise to leave a child in his family or place him in a foster-care system that has plenty of problems, too. "Everytime you let a child go home, it's a calculated risk," says a city official. "There's no nice, pat formula. Two bruises, you leave them in the house, four bruises you take him out."

Despite a central registry where hospitals and doctors can list suspected cases of child abuse, despite improved communications between social workers and police officers, despite a lot of publicity about child abuse during the past five years here, no one is claiming the problem is declining. While the number of deaths may be statistically too small to indicate a trend, the number of children admitted to Children's Hospital as suspected victims of abuse has doubled over the past four years to 58 cases in 1979.

"Ideally, no one should be able to have kids who isn't emotionally prepared for them," says one child abuse expert. "Any female from the age of 12 on up can give birth to a child. Nothing says she must be able to provide for the child, and providing financially is the least of the problems."

She believes that child-care courses taught in junior and senior high school can help young people realize just what it means to have children and can give them guidance on how to raise them. "And," she says, "people ought to give a damn about their neighbors. You don't hear a baby crying night after night and not know something is wrong."

Dr. Annette H. Ficker, a pediatrician on the Children's Hospital child-protection team, suggests parenting classes for expectant parents, "just as they have classes on childbirth. That just really concentrates on the day of birth. Perhaps we can go beyond that. We do not have a program in the District of picking up on [identifying] mothers who might have a problem when their child is born," she says.

And, she says, fathers need to be included in whatever parenting classes are offered and in family therapy once abuse occurs. "We concentrate on the mothers. A lot of times we find the fathers are troubled with economic and unemployment problems. . . . And they take it out on the child.

"We still need more therapeutic programs that involve the whole family, and not an hour of counseling one day per week.It's got to be available whenever they need a therapeutic person.

"In my experience I've found that fathers get quite upset about a child crying. They blame the child for crying, but I think the real thing that's going on is their own frustration at not knowing how to handle this, and if they could only be reassured that it is a normal thing for a child to do, and we all feel badly about it, then they wouldn't necessarily become angry about it.

"We've had a couple of cases where the children have received severe injuries leading to death when the father has thrown the child against the wall because of the child's incessant crying."

The point here is that child abuse is not declining and both as a city and as a country we've by no means exhausted all the different ways of keeping adults from injuring their children. There's a lot of fairly simple, fairly obvious things that can be done but there is no question that most of them will cost some money.

The only question is how much do we really care?