Dear master of none,
I know what you mean, too, and I think there have been some good suggestions here already. I have a couple of thoughts to add; feel free to ignore them if they don't speak to your situation.
I don't think there's anything wrong at all in advocating for your daughter; for one thing, you can't see the future--perhaps she will become a woman who is a real force for good in the world--maybe her "real education" will prepare her to do some good work that nobody else can do. Goodness knows the world's problems need some smart people working on them! I really believe that we all have a job to do in life; yours right now is being the best mother for her that you can be, and that's what you're doing.
I also think that part of her education can be having her think about our good fortune relative to the rest of the world, in terms that she can handle according to her age and sensitivity. Obviously you don't want to overwhelm her with misery, but perhaps you could help her find ways herself to make the world better a little bit at a time, even as a child. The boys write to our foster children in Senegal and Zimbabwe, they help me with charity craft projects for organisations like Save the Children and Afghans for Afghans, they help out with volunteer work that I do in our local community--it's important to us that they see that even though they are little, they can be part of a solution, too.
Another bee in my bonnet--possibly in no one else's, but who knows--is thinking about food. I agree with EandC Mom that one can't mail one's leftover Brussels sprouts to China, but I do think that one can teach one's children at least to be mindful of where their food comes from, and of how lucky we are to have enough of it. One way in which we try to encourage that mindfulness is to grow some of our own food; if this idea appeals to you, maybe you and she could grow a little vegetable garden together next year? We are lucky and have a lot of space; we always plant a few extra rows so that some of our effort in the garden goes toward growing food that we can give away.
One last thought, and I will get off my soapbox: we try very hard to make choices about purchases--toys and clothing, for instance, and ethical meat--that take into account the human and environmental costs of their production. We have explained these choices to the kids in terms appropriate to their age and level of understanding; I hope that it won't seem too political to say that we want them (when they are older) to understand that there are some senses in which the abundance we enjoy in the West has come at the expense of others, and to think about ways in which we can stop perpetuating that situation.
I do think there are things you can do to change the world without having to feel guilty about where you're sending her to school. In our family, at least, helping the kids find those things certainly constitutes part of their education.
That's all from out here in hippieville for now--hope that helps a little bit--
peace
minnie