M. J. Trow: Maxwell's Retirement (UK 2010)
From the Publisher:
For Peter 'Mad Max' Maxwell, the only mystery that has arisen so far this year at Leighford High is the question of how to use a computer. However, it soon becomes vital that he learns when some of his female pupils begin to receive threatening messages, with the anonymous sender claiming to know intimate details about the girls. Then Max starts to receive messages too... When a body is found it seems that the prank has taken a sinister turn, and the chance of Mad Max reaching retirement looks increasingly unlikely.
M. J. Trow: Maxwell's Retirement. Allison and Busby, ISBN: 9780749007669 (January, 2010), 382 p., £19.99.