The "Mortal Engines" series by Philip Reeve is good, as is the "Companions" quartet by Julia Golding. There's the "His Dark Materials" trilogy by Phillip Pullman, although it would depend on your religious views as to whether you'd want him to read them or not - they are quite "anti-Christian" and atheist (for want of a better term) in the end.
'Itch' and the new out 'Itch Rocks' by Simon Mayo are really great. Have read them myself and they've been snaffled up in Storyshack. Itch is an enthusiastic chemist and is trying to collect each element of the periodic table. It's a really good read-exciting and unusual idea too.
http://www.storyshack.org/1/post/2013/10/you-didnt-want-it-to-end.html The other one I've been talking about on the storyshack site is 'The Giver' by Lois Lowry. My daughter finished it very quickly, it really makes you think-it's a trilogy. I haven't read it myself but am about to.
Dave Shelton's 'Boy, the bear and the boat' and 'good dog, bad dog' are graphic novels-really great and good for encouraging reading. I was at Folk east with 'Good dog bad dog' (again, a series) and one child sat in a chair and read the whole thing!
The Young Bond series by Charlie Higson might be good if he enjoyed Alex Rider. There's also a Young Sherlock Holmes series - not sure of the author. Also have a look at the other thread on here for 13 year old boys - some good suggestions.
Recommendations please. The boy in question is slightly 'young' for his age and not a big reader so isn't really into adult books yet. He has previously liked things such as Diary of a Wimpy Kid, also the Alex Rider novels and Percy Jackson. He also likes annuals. Is there anything a bit more grown up than this but not aimed at adults?