Looking for books for Ben

I'm on the look out for book series that inspire Ben to read. He's at a difficult stage, while he can read almost anything I put in front of him, but he doesn't enjoy much of it. I want him to be a passionate reader like I am, so I am looking for series that he won't want to put down.

So far the series that have done that for him are:

Enid Blyton's, The Magic Faraway Tree and The Wishing Chair.
J.C. Greenburg's, Andrew Lost series.
Ron Roy's A-Z Mysteries.

Now I am looking for more series for him. One of the librarian's recommended, The Animormophs. Since the series was unknown to me, I borrowed one from the library and read it. Decided that this is not a series that I am going to give my 7 year olds to read. Books that refer to a girl as a "skank" are not what I want Ben reading.

Currently I have the following books sitting in my pile to review for Ben. (Notice that I don't have a list for Shira? That's because she has a list of books on her to read list that I already know. She's finds far more to keep her enthralled than Ben does. Right now she's reading Lemony Snickett).

Kate McMullan's Dragon Slayers' Academy.
Enid Blyton's Adventure Series.
Louis Sachar's Wayside School series
Louis Slobodkin's Spaceship under the apple tree series.
Eleanor Cameron's Mushroom Planet series.
Ruthven Todd's Space Cat series.
Ellen Macgregor's Miss Pickerell books
The Danny Dunn series by Jay Williams and Raymond Abrashkin.

Ben appears to really enjoy Sci-fi, so that's why this list is heavily loaded with that genre. If you have any series that enthralled your children, please let me know.