The posters are still there, taped to the window of the Aspsen Hill barber-shop asking for someone to come forward with information to help solve the killing of Kathy Lynn Beatty.

The police still believe someone will, and her mother prays that it is sc. "The police seemed so sure in the beginning that they would find the person responsible, but now I am not so sure," said Patricia Beaty. So far there is no answer to who left her 15-year-old daughter dying from head injuries in the rocky area behind the K-Mart in Aspen Hill.

Kathy didn't die until 11 days later in the intensive care unit at Suburban Hospital. "The hospital personnel led us to believe that she would be able to talk. That's what we needed - a little break," said Maj. Wayne Brown, chief of the criminal investigations division of the Montgomery County Police.

It was July 24, 1975, when Kathy received the fatal blow to her head and was left lying behind the K-Mart at Georgia and Connecticut Avenues. . She and her mother and older sister were just back from vacation in Atlantic City. A friend of her mother's was a contender in the millionaire lottery drawing to be held in Baltimore that night, and her mother was going to Baltimore. Kathy and her sister decided to stay home.

Her mother last saw her about 4 p.m. Kathy had been inside all day watching television, "and she asked me if she could go outside and ride her bike," said Mrs. Beatty. Her mother said she could, invited her to Baltimore again, and told her to fix her own supper since Kathy declined again.

"I said I would be home at 9. She knew she had to be home by 8:30, because she wasn't allowed out after dark. We said goodbye and she went off on her bike," her mother recalled.

Instead of 9 p.m., it was closer to 11 when Mrs. Beatty returned, and when she saw the dark house, she was frightened, she said. but when she turned on the lights there was a note from Kathy saying she had gone to a friend's and would be back at 10 p.m. It was raining, and Kathy's mother assumed her daughter was waiting for a ride home.

She headed for the friend's house, but when she arrived. Kathy wasn't there. "The children said she had been there but had left," said Mrs. Beatty. As it happened, Kathy had not been there at all. "I think they were trying to cover for her."

At that point, she began to worry again, she said. She called other friends of her daughter until she had only one more to try - a boy on whom Kathy had a crush. The two had been sweethearts in 8th grade, and Kathy might have found an excuse to be wherever he had been and that he might have seen her.

The boy and a friend were supposed to be sleeping outside in a camper, she said the boy's father told her. When the boy's father checked outside, the boys were not there, she said. She asked him to call when they returned and began driving around, looking for Kathy.

She looked at Parkland Junior High School and drove by the K-Mart. Kathy was infatuated with mini-bikes and would go up to the store to look at them, she said. She said she also kept returning to the house, hoping Kathy would have called.

On one of her outings, she encountered a police officer, "I told him what the problem was and asked him if he would go up to K-Mart. I had been up there, but it had been so dark," she said. The police officer told her to go home and wait for an hour. If she did not hear from him, it would mean that he hadn't found Kathy and she should file a missing person report, she said.

That was what she did. Then she sat waiting for dawn, so she called call the Boy's house again. When she did call, about 7 a.m., the boy came to the phone and said that he had not seen Kathy either.

Kathy's older sister, Theresa, called her boyfriend. Together they went up to search the area around K-Mart."I didn't have much hope there," said her mother. "I didn't think she would be at K-Mart." But Theresa and Theresa's boyfriend found her purse nearby.

"Her boyfriend was running to K-Mart to call the police, when he heard. Theresa screaming her head off," said Mrs. Beatty. Theresa, just turned 17, had found her sister lying in a ditch that runs through the wooded area behind the store with a depressed fracture of the skull. "Kathy was barely alive," said her mother.

Theresa's boyfriend ran back, then called the police, an ambulance and Mrs. Beatty. He didn't tell her that Kathy was hurt. As she was driving toward the K-Mart, an ambulance passed. Mrs. Beatty said she pulled over and said to herself," Dear God, don't let it go to K-Mart."

Kathy died of complications, including blood poisoning. "At that point she was too weak to live," said her mother.

"We feel and have community," said Brown. There were several persons who saw her the night she disappeared, about 8:30 p.m. near Parkland Junior High School. Several of them, youngsters Kathy's age, refused to take polygraph tests.

A boy who lived next door had seen Kathy at home about 6:30 or 7 p.m. the night she received the injuries. He had brought her a skirt from Ocean City, chatted with her awhile, then left, said her mother. After that, she is not sure what happened. Although several youngsters said they saw her at the school, "none of them claimed they were with," Mrs. Beatty said.

"We feel sure that Kathy would not have gone up to K-Mart alone," said her mother. For one thing, although the area was littered with broken glass and stones, she was barefoot, her mother said. "I think someone down at Parkland Junior High that night must be responsible for her death. She wouldn't have gotten in a car with a stranger and she wouldn't have gone up to K-Mart by herself," her mother said.

Brown thinks that it may not have been meant to end the way it did. "We're still working on that. We still have some investigative techniques to apply," he said. "I have always felt that someone should come forward on that case."

Kathy had been sexually assaulted but not raped. More specifically than that, police will not say. "I have a feeling that the person or persons who did it didn't intend to kill her," said Brown. "It's highly possible that she ran from her assailant and fell against a blunt object. I've always felt the result wasn't intended, and that would be mitigating, if a person came forward to ease his or her conscience," he said.

"We've interviewed hundreds of people, and we have ideas about who was involved," said Brown.

Life goes on, said Mrs. Beatty, but Kathy's death has been hard on her and very hard on Theresa. "Life will never be the same for me, a part of me has died," said Mrs. Beatty.

In the hospital, Kathy never regained consciousness. "We talked and hoped and prayed that she could hear," her mother said.

"Everyone liked her. I don't understand why they had to kill her," said Mrs. Beatty. "I think somebody knows. . . . . I have a feeling somebody knows who's responsible and is not talking. I hope somebody will come forward."