You're right that "vitamin for her" or any general woman's multi is recommended for those women 18 and over... they typically have herbs that would help to balance hormones, but can put a teenager's hormones into a tizzy because they are in a state of flux as it is. ;-)
You're right that a teen multivitamin would be your best bet and you're right that One A Day isn't known for the most natural ingredients... but there are other brands that have teen multiples, too.
Overall, any answer given here as far as brands are concerned will just be personal opinion (I can give you my opinion if you'd like). There are many higher quality companies out there that are readily available and well priced... just make sure the company has a good rating with either the GMP (Good Manufacturing Practices) or USP (U.S. Pharmacopoeia), as those are the main quality assurance organizations (USP is for the U.S., GMP is for the U.S. and worldwide). That'll be the best way to make sure you get a good quality teen multi that will be ideal for you. Good luck and I hope I helped!