The Changeling. Robin Jenkins

Thirteen-year-old Tom Curdie, the product of a Glasgow slum, is on probation for theft. His teachers admit that he is clever, but only one, Charlie Forbes, sees something in Tom and his seemingly insolent smile. So, Forbes decides to take Tom on holiday with his own family, with tragic consequences.
From one of Scotland's greatest writers, The Changeling explores how goodness and innocence is compromised when faced with the pressures of growing up and becoming part of society.