Joan is energetically awful, deflated temporarily by her father's refusal to have her live with him and the discovery that he has a girl-friend. When she's turned down for a speaking part in the class production of The Pied Piper, she finds a new companionship with the rest of the 'left-outs', cast as rats, who develop their own play and become a formidable force against the taunts of other children. The way these left-outs flourish and develop is both funny and moving.
Links:
[1] http://booksforkeeps.co.uk/childrens-books/the-left-outs
[2] http://booksforkeeps.co.uk/issue/68
[3] http://booksforkeeps.co.uk/member/adrian-jackson