How Do You Explain The Birds and The Bees?

The other night when I had finally sat down to the TV to watch my favorite, The Bachelor, lunches were made, exercise was done, homework checked, dinner dishes were put away and all was well with the world, well for at least 5 minutes. I was happily drinking my smoothie and just plain satisfied, with my husband upstairs in his man room watching reruns of Mash and my daughter in the living room watching, "The Secret Life of American Teenager", when my daughter comes in the family room and asks me, "Mom, what is Or#! S#x??" I'm like I didn't just hear that? Hey, isn't secret life on the Family Channel? My eyes bugged out like one of those cartoon characters, I had the greatest urge to pull the cover over my head, but I had to compose myself quickly. Gads, what would I say? I thought of making something up. Something like, if you eat something really really good like chocolate and it taste so great that is what OS is! But I knew she'd ask her friends in school the next day, and who better than her mother to tell her what it is, right? But why am I so squeamish? When she was about 9 or 10 it was time to tell her about the birds and the bees stuff. It was a no you do it game between me and my husband, so we went to Barnes and Noble and bought her a book that would answer all her questions about men and women. We took our prize purchase home, left it in the bag and told her to go upstairs and read it and if you have any question you can come down and ask us. Now isn't that all neat and tidy? So when she wanted to know what OS was, I was tempted to say, didn't that book cover it? But instead, I said, "It's when you kiss a pee-pee," in my most calmest voice. Yuck she says and I think I must have been making all kinds of faces, because she said, Oh mom, you don't have to be so silly about it, like she was 25 or something. Just then my husband comes downstairs and says what's all the fuss about, when my daughter says, I was just asking was OS was. My husband, without skipping a beat says, it's when you s--k a guy's pen!s. Oh my dog! Oh my dog! I'm like major cringing! Geez, do you have to be sooooo blunt! Are there any sane people in this house!?? I then tell in her in no uncertain terms that if you do OS, you can get all kinds of diseases and even cancer (this word is whispered)! So don't do it!!
Why is it so hard to explain these things? I guess I didn't learn well from my mother, (she was kinda of Victorian, bless her heart!). Whenever I mention s-x to her, she would mumble something about dogs and puppies. Ummm, dogs and puppies, that can't be so bad, right?
How did you explain the birds and the bees-I think there should be classes that parents can attend so we can learn how to tell our kids in a rational mature way, instead of either giggling like crazy or hiding out in fear!