How far is sex education is correct from an Islamic perspective?

Sex education should start in the home with your parents educating you first, before the school system does (especially if it is an un-Islamic school). However, the sex education communicated to children MUST be age-appropriate. If sex education is left to peers and schools in the West, it is usual that the information given is not within Islamic principles Any other physical forms of information that relate to marital relations should be left until the person seeks to get married. They should be well prepared for this and should not shy away from searching for Islamically appropriate information on this issue.

Read more on MMC