Hugo recommends Captain Underpants and the Revolting Revenge of the Radioactive Robo-Boxers by Dav Pilkey.
It is really funny! There is a fliporama in the book which makes the images look like they move.
Eric recommends Demelza and the Spectre Detectors by Holly Rivers.
I heard Dermot O'Leary doing a "book interview" with a nine-year old girl about this book. She was fascinated by its mystery, Demelza's inventing skills (to include a machine hand that would write out her homework), it being partly a ghost store, but mainly, because she liked Demelza's character. I am about halfway through it and am thoroughly enjoying it!
Recommended for 9+.