PP here. Also the Time Warp Trio series is an easy, funny, interesting read for boys this age.

My 9 year old LOVED the Oragami Yoda series and Timmy Failure. He is now enjoying the Riot brothers. The Who Was series for biographies is also a hit. He's currently reading Who Was Steve Irwin (AKA Crocodile Hunter). The Clementine Series has also grabbed his Interest as has Narnia.

If your son is reluctant, I would try the Oragami Yoda series and Timmy Failure. They are funny, and have some illustrations so they won't overwhelm him with just pages and pages of textd. My son is s good reader, but he's more likely to pick up an "easy read" at home than a Novel. He reads both, and with a reluctant reader, you want him reading without you pressuring him to read a certain type of book.

Is he more interested in non-fiction? Because that might be a better route into reading, if its the case.

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Look for things like bios of favorite sports stars, books about favorite animals, space, or other specific interests. Maybe he will prefer these to fiction books. Also consider magazines--NatGeo kids, etc.

The warriors series books.

Peter and the starcatchers.

The Guys Read series is great!

I hate that they market these books for girls or boys specifically, but there are good stories supported with illustrations:
http://www.amazon.com/Illustrated-Stories-Boys-Lesley-Sims/dp/0794514200

Is he more interested in non-fiction? Because that might be a better route into reading, if its the case.

Series of Unfortunately Events (Lemony Snickets)

Wayside School

Holes

Frindle

Really focus on what he cares about and find books and magazines in that zone. Also consider doing audio and graphic novels

The Black Caldron Series by Lloyd Alexander. First book is Book of Three.

What type of genre does he like, interests? That helps to narrow it down.

Has he read Harry Potter, Percy Jackson series, Diary of a Wimpy kid? Did he like those?

Since people are asking for suggestions for older boys, I have 9 year old who is a good reader but still reluctant. Any good suggestions? Thanks