Starman said:
Thanks for the suggestions. I'll have to check some of these out.
What area, generally? My background's in English education, but I know of some more general things, too.
As someone mentioned, Kozol's good for some inspiration and agitation.
I'm an educational history person, so though there might be a hundred books I could recommend, I might just suggest one: "Education and Social Change" by John L. Rury. It's short--maybe too short, actually, if this is your first trip through the history of formal education in the US, but it should give you some signposts about where we've been.
Theodore (Ted) Sizer's "Horace" books, though a bit older now, are good for getting people to think about what's important in education.
I'd also encourage you to look into any one of the numerous books about standardized testing. Though this isn't "philosophy" per se, it's hard to understate the extent to which standardized testing affects K-12 education today. "Standardized Minds," the author of which I forget (Saks?), is considered pretty good.
These books are probably as much "policy" as "philosophy." If you want "real" philosophy, Dewey, though often mocked and caricatured, is pretty much essential to understanding twentieth-century education movements (and reactions to them). Many of the analytical philosophers, such as Aristotle, Plato, Kant, and Mill, have important things to say about education, whether directly, like Plato, or more generally. Though there are many holes, I feel, in her thinking, Nel Noddings and her idea of "caring" in education have been very influential in the last couple of decades.