It was heard at several different intervals over the school year. The high school students and staff lived in fear of it. They'd studied the phenomena carefully and could predict, approximately when it would occur. But once in a while there would be an unexpected rumble and it would begin. The terror came from the music wing, more specifically the band room. The surrounding classrooms did their best to survive.
Early one morning there was a familiar shaking deep in the foundation of the school. Chaos began within the walls. Students were crowded into classrooms, the rooms were locked, and everybody waited with bated breath for the terror to be over. Then, from the very heart of the band room the noise began. The sound of nails on a chalkboard. No, the sound of a dentist's drill. No, the sound of some creature mortally wounded and giving its death cry. "Happy birthday to you. Happy birthday to you."