Sex Education

Personally, I believe sex ed should begin in late elementary school. Many children begin puberty without having any ideas what is going on in their bodies. If schools don't teach sex ed until middle/high school, almost all of the students will have already hit puberty and had to go through this awkward time in their life unprepared.
I'm not saying start teaching about condoms and STDs that early, but at least begin to acknowledge that boys and girls aren't exactly the same.
I believe that in middle school is when students need to be taught about birth control and STDs. They need to understand the risks of sex before they start having it. Many people may think that middle school age children are not likely to be sexually active, but when I went through middle school we had at least 5 girls pregnant, one of them being a 6th grader. Perhaps if they had been informed about their birth contol options, these unplanned pregnancies could have prevented.
Sex shouldn't be considered "dirty" or "taboo" but it should be considered something that should be saved for a committed relationship. If sex is taught to be "taboo", children will not ask questions because they might be too embarassed, and just try to figure things out on their own. They should be taught the risks, stresses, and conflicts involved in casual sex, but also how to have safe sex.