I know someone in the Stanford program currently, so here's a guest post. Send me a message if you'd like more info.
Hi, I am a PhD student in the Philosophy of Education program at Stanford now. Eamonn Callan is my advisor, and he is actually the only philosopher of education in the School of Education at Stanford right now. I am the only PhD student in phil of ed at Stanford right now also. Rob Reich also does work in philosophy of education but he is in the political science department and doesn't take in education PhD students as far as I know. So it's a very tiny program. If you are interested in literacy/language, I would recommend pursuing a degree in that area rather than philosophy. Academic positions in phil of ed are incredibly limited, whereas there are more openings in language/literacy. So strictly with regards to your long-term job prospects, you'd be better off with a degree in the other area. If you apply to the language and literacy education program at Stanford, you would still have the option of pursuing a MA in Philosophy while here if you wanted to. You could also work with Professor Callan potentially or others in the philosophy department who work on language. Stanford encourages interdisciplinary work, so you have a lot of freedom regarding the courses you take and the work you do once you are here.