Something terrible is happening to children here and their parents, with the normal anguish of parents, want to know what it is.

In Coeur d'Alene, 30 miles away, 8-year-old Lore Wilson struggles to write the alphabet. After five minutes and just six scrawled letters on the paper she gives up in tears of frustration.

"She used to be able to recite the whole thing from memory," says Judith Wilson, watching her daughter's efforts. "Now she has trouble remembering and it upsets her. She seems to be going backwards and we don't know why."

In Spokane, just across the state line in Washington, Lonnie Bruss also worries about her 6-year-old daughter Katina.

"I tell her to check to see if a window is open and she comes back with a diaper for the baby," said Bruss."She doesn't seem to understand things and she forgets right away. I can't understand what's going on in her mind."

In another part of Spokane, James and Pat Oberg have had to put their two sons into special classes for slow and problem learners. "They can't seem to concentrate on anything or remember what you say to them," said the boys' father.

The children with learning problems and faulty memories have this in common; all were born or raised near the giant Bunker Hill Co. lead smelter here, deep in the heart of Idaho's rugged northern Panhandle. The parents though they lack hard medical evidence, have suspicions.

Lead is a highly toxic heavy metal whose effects on children have raised national concern in the last few years. Medical experts have determined that lead can cause nerve, brain and kidney damage and in high doses it can kill.

In the absence of conclusive information, the Bunker Hill situation here is becoming a classic example of the ambiguities and anguish that can often surround an environmental pollution issue.

Several years ago, federal medical experts identified the Bunker Hill smelter as the source of the nation's worst mass exposire of children to high levels of lead.

A 1974 study by the Center for Disease Control found more than 400 out of 1,000 children here had dangerously high lead levels in their bodies.

This was followed by another study, the Shoshone Project, cosponsored by the state govenment and the lead company. The now-disputed study concluded that -- notwithstanding the heavy pollution -- children near the smelter were not damaged by it.

That's where the matter rested, until some parents began to perceive new learning disabilities in their children. It is impossible to be precise, but parents of more than 30 children, interviewed here and in other locations where they have moved, report similar troubling symptoms. Yet they lack medical evidence to confirm any connection with lead exposure.

Without neurological testing, it is impossible to determine whether the problems related by the parents are connected with their children's exposure to lead, or something else that may be the cause of the learning disabilities.

"It is a thoroughly human reaction to blame the pollution as the answer for every problem troubling anyone nearby," said Dr. Kathleen Kreiss, the CDC'S acting director for special studies.

Parents, upset by their children's failure to show adequate progress in learning, may in desperation put the blame for the problems on the smelter, Kreiss said.

Yet, other medical authorities say there are some troubling aspects about the Kellogg situation.

"Given some of the lead levels they found in the blood of those children in Kellogg it isn't all that surprising those kids are showing signs of retardation," said Dr. Ellen Silbergeld.

Silbergeld, an expert on the effects of lead in children for the National Institute of Mental Health, dismissed as "meaningless" the fact that blood lead levels in the children had dropped sharply since the 1974 testing. Measuring lead in a child's blood after an exposure does not tell the extent of brain damage from the heavy metal, she said.

But blood lead levels do tell the extent of a child's exposure, experts said. In 1974, the federal investigators found more than 400 children around the smelter with blood lead levels measuring 40 micrograms or more per deciliter, with some up to 175 micrograms.

Last year, the Environmental Protection Agency said any blood lead level over 30 micrograms could cause hidden damage to a child's nervous system. Other specialists have said damage occurs at even lower lead levels.

"We are getting to the point where we can show the effects of lead on children's brains at lower and lower levels," said Dr. Herbert Needleman, of Children's Hospital in Boston.

Paul Whelan, a Seattle attorney representing two families whose nine children lived near the smelter, contends that doctors who performed neurological examinations found all nine children have nerve or brain impairment. The families, whose children had high blood lead levels in the 1974 test, are suing the smelter for $20 million.

"In some cases their IQS dropped 10 or 15 points," Whelan claimed. "The economic effect of a loss like that is enormous over a lifetime. How do you measure what you won't ever be?"

Idaho officials, however, see no need to conduct neurological followup tests on other children who had high lead levels in 1974.

"We haven't heard of any problems," said Dr. J. A. Mather, the state medical official assigned to recommend any additional tests. "For some reason the children of Kellogg seem to be protected against the effects of lead. I really don't know why."

State officials and spokesmen for the Bunker Hill Co. cite the medical study conducted by the Shoshone Project on children who live near the smelter as proof that no long-term lead problem exists among the youngsters.

The study was set up jointly by the state and Bunker Hill following the 1974 lead scare. In its report in 1975, the Shoshone Project concluded:

"At the present time and in our best judgments we do not feel any permanent clinical impairment or illness has occurred [in the children]. Further, it is not likely to occur in the future due to this particular exposure."

Since then, Mather has conducted blood lead tests among a small number of children living very close to the smelter. He said blood lead levels have dropped here and there are no plans for any additional neurological testing of children.

But lead continues to pollute here. Lead dust coats houses, cars and trees near the smelter. Federal air monitors show high lead levels around the smelter. In January of this year, one sample at the Silver King Elementary School, which is just below the smelter stacks, registered 10 times the federal safety levels for airborne lead.

"It would seem that there are a lot of children here who have learning problems. We do see quite a few slow learners," said Richard Tank, principal of the school.

But Tank said he had not asked district school officials for any neurological tests to determine if the children's learning problems are related to lead exposure.

"It's a delicate issue," he said. "If I asked for the tests the answer would be no and I don't have the authority to order them myself."

The Bunker Hill smelter is the largest employer in the northern half of the state, with nearly 2,000 jobs. Smelter officials have repeatedly threatened to shut the plant if they are pressured by environmental regulations.

Dr. Phillip Landrigan, the senior federal official assigned to the Shoshone study, now contends that it followed questionable scientific methodology that caused the results to underestimate possible lead problems in the children.

Landrigan also said dozens of children living closest to the smelter with high lead exposures in 1974 were left out of the study.

"If the study had been done properly the results would have showed a much more severe lead problem in the children in Kellogg;" he said. "I wish my name had never been associated with it."

A Bunker Hill spokesman said the company put up all the money for the study -- about $125,000, including the project director's $5,000 monthly salary.

But the company declared; "The Bunker Hill Co. had absolutely nothing to do with any medical or environmental selection of subjects or conditions relative to any aspect of the projects that were being conducted by various state and federal agencies on the Shoshone Project."

And the study's director, Dr. Glen Wegner, a Boise physician and attorney said the study was fair. "It was a tough situation to referee," he said. "If we erred it was on the side of being too tough."

In any event, parents and some medical experts say a new study is necessary to determine, once and for all, whether the children bear a terrible legacy from their exposure here to lead years ago.