This is an excellent continuation of the Dragon School series.
This is the omnibus for four of the novellas, and I enjoyed having them bound in one volume. However, the individual books are very short, and I think they would be enjoyable for hesitant readers who are intimidated by larger books, but would like a slightly more mature content. It's nice that this series is available in both formats.
It is also a nice read for my 11-year old, who is ready to begin reading books with slightly more mature themes, but isn't necessarily ready for Heavy Topics. This book doesn't shy away from hinting at certain themes - disability, slavery, love, addiction, racism, and self-sacrifice are all approached in the series - but it is done in a matter-of fact way that doesn't feel confrontational or stressful for young readers. When these things are set in a fantasy world, it makes them much less scary and easier to process. (And example of how one of these themes is approached: our protagonist is traveling to another county, and learns that the drinking water there has addictive properties, and finds herself compelled to carry the water with her when she returns home while she figures out how to wean herself off of it.)