a book for teens and tweens

A book I bought my pre-teen son who is not a reading ferru !! quite the contrary ...
he really hooked, he read it in 2 days !! Now and then he asks the entire collection ...
I think it is a series of stories in which teens identify themselves, all conducted with great humor and easy to read.
That's it, I managed to give him the desire to read, to interresser to written stories and not necessarily television! hope it lasts ...
He adores!