Childhood in the 21st century has changed completely, as the outgoing children’s laureate Frank Cottrell-Boyce knows from his work on the front line of schools, libraries and prisons. But, writes Robert McCrum , his dispatches from two years in the job resist the usual scaremongering, and remind us of the power of good stories I t doesn’t take much to make a good childhood,” writes Frank Cottrell-Boyce. “It just takes attention.” In the week in which the government announced plans to ban social