Raising Teenage Daughters in the Age of Provative Dress and Sexism

I am raising a 14 year old daughter who is one of the sweetest, kindest kids on the planet. She will ask me sometimes if its ok if she wears a skirt that is to short for her or jeans that are to tight. I tell her no that she is a young teenager and those clothes are unacceptable. Some people say I am restricting her freedom because I refuse to allow her to dress like an adult woman. She is not an adult she is 14. I have lots of help because my daughter has two older sisters and three older brothers plus a load of cousins who also tell her "NO"
Does this upset my daughter? Not really I think she likes when I tell her "NO" because it sets limits and also gives her an excuse if she doesn't want to dress a certain way but peer pressure is very strong. She can then make me out to be the bad guy. I think that is the way it is with most teenagers. They may fight and agrue but they know in the end that you have their best interests at heart. They also will never remember the times you told them "NO" but they will thank you for setting boundries.
Television is another issue. I am amazed at how many shows on TV are either racist or sexist or both. I have one rule and that is Nothing racist or sexist on tv. I am not talking about movies like "To Kill a Mockingbird" or movies that address either sexism or racism but movies and cartoons that use sexism or racism for entertainment. I don't mind my daughter watching Avatior because it has strong female characters.
Avaitor has several strong female main characters that are not filled with sexual stereotypes. I love Kataria the main female character who is a water bender. She is respected by all the characters on the show and she is a positive character for little girls to emulate.
My daughter is more likely to gripe about TV then she is about clothes and frankly I believe the images that TV portrays are worse for her in the long run then the clothes that seek to grow our daughters up before their time.
Its time for Television to remember that half the audience is females and we are the largest buyers. We are the shoppers and we need to make sure that advertisors know we will no longer accept their sexism on TV.