The If Machine: Philosophical Enquiry in the Classroom
by Peter Worley
Games for Thinking
by Robert Fisher
The Philosophy Book: Big Ideas, Simply Expained
by Will Buckingham, Douglas Burnham, Peter J King, Clive Hill, Marcus Weeks and John Marenbon
The Little book of Thunks
by Ian Gilbert
Useful or Interesting Websites
Sapere: run good P4C training courses, interesting research on the impact of the use of P4C.
The Philosophy Foundation: a charity that trains Philosophy graduates to lead Philosophical Enquiries with pupils in the classroom.
The Philosophy Man: lots of lovely free stuff, and a weekly email bulletin you can sign up to.
P4C.com: a cooperative providing resources for P4C. Some free samples available, some only for members. Have just begun a parents area - will be interesting to see how it develops.