Do you know this one? I’ve never read it but kids often tell me their teacher read it to them in 2nd grade and they loved it.
A compilation of three tales which relate the fantastic adventures of Elmer Elevator and a baby flying dragon named Boris. (TitlePeek, Follett School Solutions, 2017)
Reading level 5.2, but my guess is that it’s lower than that. (See Laura G for more info as she’s used it with kids.)