WOW - im a personal development, health and phys ed teacher in australia and we dont preach abstinence. We do teach it as one of the many forms of contraception that can be used when sexually active.
Sex ed is a major unit in this sujbect, we teach them about being emotionally mature to make such a decision, how to say no, how to understand if you are or arent ready, having the confidence to end a relationship if sex is pushed upon an individual.
We also teach students about all the forms of contraception that is available to both MALES and FEMALES!! condoms, pill, diaphragm, IUD, depo shot, implanon, female condom, abstinence.. and also the unorthodox methods some ppl do use such as rhythm method, withdrawal etc.
We teach that is both the males and females decision to be responsible when it comes to be sexually safe. It shouldn't lie on the males hands to provide condoms or the females responsibility to be on the pill.
God i could go on forever about this, we cant make the kids not have sex but atleast arm them with the knowledge so they know how to stay safe, be confident and resilient enough to say no when they arent comfortable with the situation.