I feel that sex education should be compulsory for all young people. While some parents may do an excellent job telling their children about sex most parents do a lousy job. Some even give their children books about cats and let them figure out the rest for themselves.
Sex is too important a subject to allow ignorance. Telling people to abstain is fine, and those who choose to abstain will not get pregnant or catch any diseases. What about those who do not abstain though? Should they suffer through ignorance?
Also what about homosexuals? There is certain to be at least one or more in every school year group, should they suffer because nobody taught them how to have anal sex safely?
There are so many other "explicit" things that parents will not tell their children that the state should do the job for them.
As for porn, there is no conclusive evidence that it does any serious harm. You could even argue that it is educational.
For example I left school able to draw and label an accurate diagram of both the male and female reproductive systems, but no teacher ever mentioned the clitoris or what it is for.
Without pornography no man would know the clitoris existed!

What's more we wouldn't care!