One 10-year-old girl was raped and a second sexually assaulted Thursday by young men at District of Columbia elementary schools, police reported yesterday.

The two attacks were apparently unrelated, but parents and teachers yesterday expressed anger and concern over what they called lack of security for the children who attend the two schools.

In an effort to provide security, the principal in one of the two schools yesterday ordered teachers to escort in groups all children who must go to school restrooms. Parents said the measure was needed to protect their children from teen-aged males who roam the elementary school halls and harass the children. According to police, the first incident occurred at Plummer Elementary School at Texas and C Streets SE when a 10-year-old girl was lured from her classroom by an unidentified male.

Police said the class was temporarily unattended when the attacker entered and told the child that she was wanted in the principal's office. When she left the room, the man pulled a knife, forced her into a wooded area across from the school and raped her.

In the second incident at Tubman Elementary School at 13th and Kenyon Streets NW, two teen-agers cornered a 10-year-old girl in the girls' restroom.Police said they stripped her and attempted to rape her but were scared away when a teacher walked in and discovered them.

School Superintendent Vincent Reed said yesterday he was concerned about the two incidents, which are being investigated by police and school security officials. "We don't have many cases like this," he said.

No more than five such incidents were reported last school year, he said.

Parents interviewed at Tubman yesterday expressed shock at the incidents. "I'm very concerned about it," said the mother of a 7-year-old girl who attends Tubman. "I worry about her being there."

Another woman, the parent of a 9-year-old boy at Tubman, said she was angered by the fact that teen-agers can even get in the school.

"It is dangerous in there. The bigger kids come in and bother the students. It's dangerous for the little boys and girls," she said.

Tubman Elementary school sits in the heart of the city. Its doors are unlocked and visitors are free to roam in and out.

"We can't lock the doors," said school principal Vivienne Shorter. She said parents and older brothers and sisters come to the school throughout the day, making it difficult to control entry.

She said it was not unusual to have older males in the school, but usually they were her students' older brothers.

Reed said the doors of the schools cannot be locked because of fire regulations.

"Anybody can walk in off the street. There are no policemen in the school. Our teachers aren't trained to be policemen," he said.

There is a security force for city schools, but it is not large enough to have an officer in each school, especially at the elementary level, officials say. In secondary schools, community aides help in patrolling halls to keep out intruders.

Shorter said that in the past teachers in her school regularly were supposed to escort students to the restrooms. However, several parents said their children have told them that the teachers have not been doing so.

She said she emphasized that policy to the teachers yesterday.

One Tubman Elementary School parent said the incident has frightened some of the girls at the school. She said she talked with a 10-year-old friend of the girl who was attacked. "She said she was going to ask her mother to transfer her to another school," the woman said.

Ellsworth Mitchell, principal of Plummer Elementary School, said Thursday's incident was the first of its kind to occur at the school. "We are all concerned about it," he said.