Wicked! by Cooper, Jilly published by Corgi (2007) [Mass Market Paperback]

At Bagley Hall, a notoriously wild, but increasingly academic, independent, crammed with the children of the famous, trouble is afoot. The ambitious and fatally attractive headmaster, Hengist Brett-Taylor, hatches a plan to share the facilities of his school with Larkminster Comprehensive - known locally, as 'Larks'. His reasons for doing so are purely financial, but he is encouraged by the opportunities the scheme gives him for frequent meetings with Janna Curtis, the dynamic new head of Larks, who has been drafted in to save what is a fast-sinking school from closure. Janna is young, pretty, enthusiastic and vastly brave - and she will do anything to rescue her demoralised, run-down and cash-strapped school.

Neither parents nor staff of either school are too keen on this radical move,although some can see the possible financial advantages. For the students, however, it offers great opportunities to get up to even more mayhem than usual.