Modesty and wearing a bikini?

I need some help. I'm a 15-year-old girl and I've been wearing one-pieces or tankinis my whole life. Lately I've been wanting to wear a bikini, especially because I play beach volleyball. My mom and dad, though, are kind of iffy about it. Their main concern is modesty and trying to attract boys. Honestly, I promise, I'm not trying to be like that. I just like bikinis, I think they're cute, and I want to wear one. I know in the Bible it says to be modest, not to be a "stumbling block" to anyone, and to respect/obey your parents. I really don't want to disappoint or disrespect my mom and dad, but I want to wear a bikini. Thoughts please? From a Christian perspective of course...