Burton's Grill on Boylston St. is an "American Restaurant" but they offer a separate menu that is entirely vegetarian. Often a good choice to meet the best of both worlds. I have always enjoyed any meal I had there and would be very comfortable bringing guests there. I am sure there are others that will be suggested, but since I am a "fish, meat, and more fish" guy myself I have limited knowledge of the vegetarian options. I knew of this one and had to share it, though, because I think it is a good one.

Shandy1977,

Thanks so much! I really appreciate it!

Boston is small and the North End is not far from Back Bay, unless you are trying to walk in our current ongoing snow emergency conditions! Lots of great vegetarian choices on the menus there.

I also just noticed that Sel de la Terre in Back Bay---a wonderful place!!--states on their menu that they have a vegetarian menu available. You could have the carnivore's delight while they enjoy the amazing cooking and service of the vegetarian menu. If you want to break the bank, you can take them to L'Espalier where the tasting menu is also offered in a vegetarian version. However, since Sel de la Terre is run by the same people, you get all the amazing quality at a more reasonable---altho by no means inexpensive--price.

Casual: The Other Side Cafe, Newbury St.

Ethnic: Tapeo, tapas on Newbury St.
Chili Duck, Thai on Boylston St.
Kashmir, Indian on Newbury St. and some others.

Most all restaurants offer some vegetarian options, but some are better than others. For instance, Sonsie, Newbury St., is a fun, active restaurants and has some pizza, pasta, portobello mushroom dishes. Joe's American Bar, Newbury St., same--pasta, pizza, macaroni and cheese.

Also Fire+Ice, Berkeley St.--you choose vegetables (or meat) and sauce to be grilled.

There's a Wagamama in the Prudential Center.

It all depends on what atmosphere you want and what your daughters and her friends like to eat.

I'd check out chowhound.com and be very specific about what you are in search of. They have never steered me wrong! Have a great time in Back Bay.

Sel de la Terre comes to mind. Also, I just "discovered" Vlora on Boylston Street. I've been ignoring this restaurant for years and finally just had lunch there the other day with a friend because we were running out of places to try and although it is "underground", it was brighter(because of the huge skylight) than street level restaurants that day, decided to try it. Boy, was it good. They had several vegetarian appetizer dishes that honestly, were fairly big. I could imagine going back there and just ordering a whole bunch of apps and sharing, to get various flavors.

may I recommend Erbaluce, for something a little more unique.
http://www.erbaluce-boston.com/
It's Italian, but a modern, lighter style, very heavily focused on vegetables.