Can't trust my kids' pop music education to the schools

My son DJ and one of his classmates have developed a liking for the Beatles. I knew all those CDs I played him at bedtime would make a difference :-). Anyway, they were asking their music teacher at school some questions about the group and the teacher told them that all but one of the Beatles is dead. Huh? I assured DJ that two of the Beatles are still alive but he was skeptical. He is at that age where he thinks the teacher knows more than I do. I guess I have to renew my efforts to teach them about some of my favorite music.