There are a lot of good suggestions here already, my kid never got into wimpy kid, but is a bookworm, about to turn 10. Some books we've liked; (with Mild summaries written at 6am)
Minecraft woodsword books is about a group of kids that go in and out of a VR Minecraft game
Harry Potter (you can dislike the author and still like the story)
Percy Jackson is about a present day Greek demigod, growing up.
Hotel flamingo is about animals working at a hotel
Dragons of wrenly
Puppy place.
Storm dragons.
Silver arrow (train story)