Some interesting reading: "Why Gender Matters" by Leonard Sax - focus is mostly on the benefits to boys of boys only education especially in early elementary. The benefits to girls seems to be more in junior high years. He has a website too.
www.whygendermatters.com Another book... "Gender in Policy and Practice" is a compilation of articles mostly saying that there isn't a lot of evidence that single-sex education has many benefits except with kids with the typical high risk factors. It is very dry - I had a hard time staying interested in it so haven't made much progress on that book and can't give a much a recommendation but it did counter much of what Sax claimed.
