Sawyer and his friends, Elliot and Sylvie, are caught up in another adventure when Sawyer's grandfather takes them to Mars to search for Sylvie's missing father. Sylvie has seen a partial message from her father that included phrases such as "...held against my will..." and "Tell Sylvie not to..." Although she knows that her father is probably saying for her not to worry, she is very concerned and leaps at the chance to find him. Along the way they drop off some polar bears at an unexpected location, pick up a stranded traveler from Pluto, and finally get to see Sylvie's old apartment on Mars. But they also find out that there is a major soccer match between the Mars team and the Pluto team, which will be followed by a vote on whether or not to ban the Plutonians from the Intergalactic Soccer Federation. Since Pluto was demoted to the status of dwarf planet, its inhabitants are already angry with the Martians and the results of the soccer game and the vote could lead to riots, or worse.
You would think that being part stegosaurus and having plates down his back and a tail with spikes would be enough of a challenge, but Sawyer winds up playing a very important part in the crisis between the feuding planets. (I can't say more without spoiling everything.) Along the way are some surprising revelations about Sylvie's mom and dad, Sawyer's grandfather, and even Elliot. Sawyer does his best to work out a happy ending for his friends and his new acquaintances, even continuing with that trend when the kids return to Earth.
Besides being a funny story and packing in lots of action and suspense, other themes are also tackled. Sawyer is still dealing with his new status as a human/dinosaur hybrid and feels uncomfortable with all the attention he receives on Mars. Sylvie needs to resolve her feelings about her parents and their divorce. Elliot is trying to find his own identity besides just being the tall kid at school. There are also plenty of examples of how people feel about and respond to being excluded, illustrated by the extreme measures some of the Plutonians are willing to go to.
Despite the far-fetched elements of dinosaur hybrids or life on Mars (and other planets in our solar system), the Dinosaur Boy books show a lot about tweens trying to deal with family, homework, and friendship. A great addition to the chapter books in a school or classroom library, I highly recommend the series.
I read an e-book provided by the publisher through NetGalley.