I'm on Chapter 7 of my book (of 12). ????This one recommends a new way to look at the value of charter schooling (teaser: it's not about looking at the quality of individual schools). ????So I've been swimming in the previous research and writing on this subject. ????If you're interested in this subject, here are a few things you might want to check out:
Though it answers a limited question, this report by NAPCS is excellent--very thorough. It can be coupled with this CREDO report from Macke Raymond, which, importantly, considers the variation among charters.
Ted Kolderie understood the nuances of the charter achievement debate years before others. I recommend anything he's written (this especially), but here's a superb and short blog post on the subject in case you are pressed for time.
If you'd like a sense of what chartering has made possible, you might want to read Whitman's treatment of high-performing charters or Mathews' story of KIPP.
Finally, if you're like me and convinced that we have a system/industry issue (pre-order my book!), definitely check out Foster and Kaplan's Creative Destruction.