I'm looking for books to keep DS (7) busy over the summer. He really loves Enid Blyton (Famous Five and Secret Seven). What else can I suggest to him? EB's are the only English books I remember from my childhood. I get a bit lost in Waterstones looking for books for him because, although I see many I think he could read, I don't want him to read "trash" and I don't know which is which.
(I've checked a similar recent thread about childhood books but I'm after something more specific for a 7 y.o. - can be contemporary too.)