This article by GreatSchools has some fantastic recommendations for popular Fourth Grade titles, both new and old.
Fourth Grade Book Recommendations
Is your fourth grade guy (or even girl) losing interest in reading? Popular children’s author Jon Scieszka (of Stinky Cheese Man Fame) has made it a personal goal to get guys back into reading. Check out his site, GuysRead, for a list of guy-friendly books that will excite your fourth-grade reader.
CAUTION: This website is for guys of all ages. Make sure to read book descriptions before checking them out for your reader.
This website offers various interactive tools broken down by specific Language Art skill.
Interactive Language Arts Skill Builder
Reading Rockets is a great website that offers information to help parents understand the process of learning to read. You can also access list of Children's Books and author videos.
Practice comprehension strategies using online reading passages and guided interactive practice.
Into the BookThis fun website has interactive online games to practice spelling, words in context, and other language arts skills.Use this site for extra-practice on your WordlyWise words. Just choose your book and get to work. Includes word lists and games.Watch celebrities read aloud many favorite stories.