Oh, sex ed: there's no way for it not to be at least a little awkward. Sex is one of the most crucial courses that kids take in school: full of practical knowledge that they'll use for the rest of their lives. And if the sex ed they're getting is over the 'abstinence-only' variety, they'll use it for the rest of their kids' lives.
A recent Reddit thread called for stories about the "weird shit" that went down in during sex ed, and damn: from overly demonstrative teachers to remarkably inventive metaphors, these are the best ones.
Someone asked about giving a girl a blowjob and how it works. Kid behind me says, "it's like eating a hamburger sideways."
No work was done for the rest of class.