The Catholic Church officially prohibits contraception, oral sex, and masturbation!!!!
Many people, even non-religious ones, naively fell for the entire propaganda of the Alliance for the Family without even understanding what the religious fanatics who initiated the referendum were actually after. A religious fanatic (or a practicing Catholic Christian) gets upset if their child learns about contraception at school, about the existence of masturbation, sexual positions, or oral sex. This is the real reason why the religious activists who initiated the referendum wanted to ban sex education.