When should sex education begin in schools?

In many of the country the sex education has started in school but many people are not agreed with this. What should be the actual age or class in which this should be started?

where i am its the end of 7th grade. it sounds about right to me.

where i live, they had a class in the 5th grade
its never too young

I agree with mustanghotty09...Reading some of the questions on here and looking at the ages, I would have to say it needs to be started much earlier than it is.

Or maybe, concerned parents could start talking to their children about sex and about their expectations (don't have sex till you're married, use condoms if you have to, etc.).

The average fifth-grader has absolutely no idea what sex really is. Period. They don't even have anything yet, so how exactly do you expect them to understand the concept of a sperm or an egg? It's still too abstract for them - and half-baked knowledge is even worse than no knowledge at all.

i had it in fifth grade, and it was totally useless cuz everyone just giggled the whole time and the teacher never got anywhere. i'd say 6th grade is about right, cuz b4 that is just a waste of time [altho should probably have the talk b4 thn]

grade 1 seriously