@Ltryptophan you don’t need to get specific but sex is about pleasure and joy. I don’t think anyone is suggesting giving instructions or showing them porn or anything. You can’t just discuss the mechanics and miss out the emotional aspects, including pleasure though.
I actually think this is one of the problems kids get into trouble. Parents aren’t comfortable talking to their children about something that is the most natural thing in the world. If they understand that sex is an amazing part of a loving, respectful relationship and that it should be something they enjoy but that they need to treat it with the respect it deserves, they are less likely to get into trouble.
I, like many of the parents here, discussed sex with my children from when they were little and it was just a normal part of the process of growing up. They asked me questions, I answered. When a film or television programme was on and they saw something that puzzled them, they felt no shame or embarrassment in saying, “what does that mean?”. I answered as best I could. I know I have said things my kids still laugh their socks about but they are comfortable enough to tell me “do you remember when you said…, I told all my friends about that”.