VERNON-At approximately 8:20 Tuesday morning, Glen Meadow Middle School was evacuated under what the school system calls a "green alert.." All children were immediatly sent outside onto the blacktop and were there for about half an hour without their coats. Half of the seventh grade had already left on its annual field trip to see the play "Holes" in Hopatcong. Students at the school said that a seventh-grade girl found a baseball card in her pocketbook with the words "there's a bomb in the school" written on it and told one of the teachers. The school was evacuated, and police arrived with a K9 unit to investigate. Students said lockers were searched. Classes were canceled and seventh graders were eventually told to walk to nearby Cedar Mountain School while eighth graders walked to Lounsberry Hollow School, where buses were summoned to take them home. Most students returned home by 10:30 a.m. A reporter calling the board of education for more information was told to send an E-mail.