Read other letters about this article
Unless you literally remove your child from American society by homeschooling like Anonymous_Too, there is absolutely NO WAY that you will convince your child to ignore every message sent by society just because her parents say so. Parents really need to drop the idea that they have much control or influence at all over teens. Teens are influenced by (A) their peer group, and (B) what they see in magazines/TV/internet. Most teens think their parents are boring, lame, clueless, embarrassing, and out of touch, so why would they listen to what they have to say on matters of appearance and social group?? They're more likely to do the opposite. At least, that's how I was.
I was interested to read your letters because I used to be one of those girls obsessed with models and beauty, much to the chagrin of my feminist, extremely successful mother. As a kid, I wasn't allowed to have Barbies, I got chemistry sets instead, etc. I was raised to value intelligence and hard work over superficial qualities. But frankly, none of that mattered to me. I was OBSESSED with models and looking like/being one. If it's any consolation, I eventually got over that phase and I'm now an educated professional who is thoroughly embarrassed by the consumerism and superficiality of my youth. So there's hope.
BUT, the fact of the matter is that your daughters are really just making a rational calculation based on what they see around them. If they follow your advice and become, say, a scientist, they will get to live an average middle class life and probably marry a similar guy. And they'll have to work really hard to do that. If, on the other hand, they became a successful model, they would live a life of fabulous riches, fabulous travel, fabulous men, and lots and lots of POWER. Without having to do virtually any work. Is it really so shocking they would go for the latter? People aren't saints. They will usually strive to obtain the most power for the least effort.
In addition, if your daughter is gorgeous, she probably gets heaps of admiration, social status, friends, and attention because of it. If she's class valedictorian, probably no one cares except her parents. Getting straight As will not give her any social power or status whatsoever. Looking hot will.
This is all quite depressing and disappointing, but it's the way it is.
So my main point is, the influence of two parents is not enough to overcome the rest of the world. You want her to contribute to society and use her brain. But no one else does. The rest of the world would prefer that she pose in Maxim. Young girls will never stop striving for power through beauty until society stops rewarding them for doing so. So don't beat yourself up about it, it isn't your fault and there's probably not much you can do (short of homeschooling or moving to a third world country or commune).