Argument: Comprehensive sex-ed often actually encourages sex
Valerie Huber. "Opposing view: Abstinence works". USA Today. 30 July 2007 - Studies show "comprehensive" programs do little more than promote contraceptive use, spending less than 5% of their course time promoting abstinence. A recent Health and Human Services study found that "comprehensive" programs exaggerate the effectiveness of condoms and encourage a false sense of protection. Further, the study noted that one popular program promoted graphic sexual behavior such as showering together as an acceptable "abstinent" activity.
Barbara Dafoe Whitehead. "The Failure of Sex Education". The Atlantic. Oct. 1994 - there is not a shred of evidence to support the claim that noncoital sex, with or without communication, will reduce the likelihood of coitus. William Firestone, of Rutgers, who wrote the study for the Network for Family Life Education, concedes that his enthusiasm is empirically unfounded. In fact, several studies show just the opposite. Outercourse is a precursor of intercourse. But do we need studies to tell us this? Is it not graven in our memory that getting to third base vastly increases the chances of scoring a run? In fact, it could be argued that teaching noncoital sex techniques as a way of reducing the risks of coitus comes close to educational malpractice.
[...] The unifying core of comprehensive sex education is not intellectual but ideological. Its mission is to defend and extend the freedoms of the sexual revolution, and its architects are called forth from a variety of pursuits to advance this cause. At least in New Jersey, the sex-education leaders are not researchers or policy analysts or child development experts but public-sector entrepreneurs: advocates, independent consultants, family planners, freelance curriculum writers, specialty publishers, and diversity educators. However dedicated and high-minded they may be, their principal task is not to serve the public or schoolchildren but to promote their ideology.