A Prince George's County judge ordered the County School Board yesterday to provide home teaching services to a student expelled under a tough new weapons policy pending a hearing on whether the new rules are constitutional.

Circuit Judge Vincent Femia granted a preliminary injunction in the case of Derrick Lee Stevens, a 13-year-old 8th grader who was enrolled at Charles Carroll Middle School in New Carrollton. Stevens was removed from school Jan. 13 after a fight with another student near the school in which Stevens drew a penknife to defend himself, according to his attorney, Edward Garrison Neal. Neal said Stevens was attacked by a boy who was "a head taller and 50 pounds heavier."

More than 100 students have been expelled this year under the new school board policy against drugs and weapons, compared with only one student the year before. Some parents and school board members have criticized the policy regarding weapons because it does not take the circumstances of the weapons possession into account.

"If you're going to so disrupt a child's life, there ought to be fair proceedures," said Neal, who called the policy "unconstitutionally vague" and contended that it violates students' right to a fair hearing.

Under the school discipline code, which calls for mandatory expulsion for weapons possession, Stevens' case was heard Feb. 1 before Executive Assistant School Superintendent Clark Estepp. He appealed Feeney's decision to expel him to the school board Feb. 16 and notification that the expulsion was upheld was received on Tuesday.

Femia ruled that continued time out of school would do "immediate, substantial and irreperable harm," according to Neal, who sought to have Stevens immediately returned to school. School board attorney Paul M. Nussbaum, vigorously opposed that move.

"I'm of the opinion that the code of student conduct is constitutional," said Nussbaum, who added that to return Stevens to school, "would in essence destroy the effectiveness of the Code of Student Conduct" under which he was expelled.

Stevens will receive 6 hours of instruction per week from a substitute teacher beginning Wednesday, according to school spokesman Brian J. Porter.