My 9 and 6 yo dds love Hardy Boys books.

The My Father's Dragon books (rUTH sTILES gANNET) WILL BE QUICK BUT FUN READS. (sorry - capslock)
The Narnia books would prolly be a hit. And maybe if you start it as a read aloud, the Swallows and Amazons books (Arthur Ransome) Mykids really like those but they can start slow, so we do them as read alouds at night. They have had many hours of fun play sparked by those books.
I bet there are some Matt Christopher books he'd like if he likes sports at all.
Dick King-Smith has written a lot of books appealing to both boys and girls. Also look at Roald Dahl's (The Giraffe, the Pelly and Me, The Magic Finger, The Twits, etc etc)
Have fun.
