In a letter sent to students of Enloe High School on Wednesday, Principal Beth Cochran said teachers and administrators must exercise discretion and sound judgment in inviting guest speakers, but she stopped short of apologizing for a visit by a Christian evangelist who denounced Islam.

The letter said the school system was investigating a visit by Kamil Solomon, a Raleigh evangelist. Students said Solomon encouraged them to convert to Christianity and handed out pamphlets, including one titled "Do Not Marry A Muslim."

"Guest speakers can provide a wonderful enrichment opportunity for our students by bringing unique personal experiences and various points of view that can significantly enhance our students' education," Cochran wrote.

But she said the school was reviewing its guidelines on inviting speakers to ensure that "their presentations and materials are appropriate for our school environment."

Solomon's visit to classes of Robert Escamilla, a social studies teacher, created a furor among students and parents who called it an attempt to proselytize to students, which the First Amendment prohibits.

Jennifer Rudinger, the director of the state chapter of the American Civil Liberties Union, said the letter didn't go far enough.

She said the ACLU had asked the school to pledge that such events would not recur. The letter, she said, gave no such assurances.

But at least one parent said he thought Cochran's letter was an improvement over her initial response.

"I think she's hopefully on the right course," said Greg Kaszycki, whose daughter, Alyssa, was in the classroom when Solomon spoke.

Kaszycki said he felt that the students were owed an explanation, too.

"I don't think the students fully understand why it was wrong," he said. "That's who really needs to be straightened out about this."