Jennings is best; yes, the schoolboy character created by Anthony Buckeridge in the early 1950's and became a whole series of books based around his mishaps at boarding school.  I read them as a boy and still have my copies.  I am currently reading them to Joey and am, every evening, in fits of laughter, as is Joey.  Truly great comedy.  And it has aged so well despite some of the language - 'Biffo', 'Gosh', Whacko!' and so on.