The focus of most comprehensive sex education is to help teens reduce the physical consequences of sex through the use of contraception.  Therefore we would label it a Sexual Risk Reduction (SRR) approach.

The Sexual Risk Avoidance (SRA) approach is one that gives teens information and skills that are intended to help them avoid all of the possible negative consequences of teen sex, including, but not limited to pregnancy, sexually transmitted diseases and infections. The Step Up Now presentation shifts the focus from the problem to the solution: healthy boundaries, strong identities and self worth.

The Sexual Risk Avoidance approach is preferred by parents. It is also backed by the CDC:

"School systems should make programs available that will enable and encourage young people who have not engaged in sexual intercourse...to continue to:  Abstain from sexual intercourse until they are ready to establish a mutually monogamous relationship within the context of marriage.  For young people who have engaged in sexual intercourse, school programs should enable and encourage them to stop engaging in sexual intercourse until they are ready to establish a mutually monogamous relationship within the context of marriage."

As parents and educators we understand the importance of prevention when it comes to high risk behaviors.  When warning teens of the danger of smoking cigarettes we encourage them to never start smoking.  If they are already smoking we stress the importance of quitting immediately.  We do not tell them to cut back, or to make sure to smoke filtered cigarettes instead of unfiltered.  We also take this approach when it comes to drugs or alcohol, so why would we adopt a "risk reduction" approach when educating students about the risks of teen sex?