ALA Booklist (Fri Jul 01 00:00:00 CDT 2016)

Room 11 again finds itself in chaos when a near-magical hair gel goes missing prior to their talent show. Without the promise of elaborately sculpted hair, many students will not perform, jeopardizing the performance, and so cohorts Smashie and Dontel return to sleuthing, creating lists, costumes, and outlandish theories. Irrepressible Smashie frequently gets carried away, with thoughtful Dontel bringing her back. Eventually they find a series of coded messages, which they crack using newly minted math skills. Classroom dynamics and a diverse cast add a realistic element to this fast-paced tale of go-go dancing, rapid bilingual alphabetization, and general mayhem.

Kirkus Reviews

Third-grade sleuths Smashie McPerter and Dontel Marquise are back.Having found classroom pet Patches in Smashie McPerter and the Mystery of Room 11 (2015), the best friends step up again when a classmate's delicious-smelling "lengthening and molding" hair goop goes missing, threatening the success of the Third-Grade Hair Extravaganza and Musicale. Who could be taking the few precious jars of Herr Goop? Smashie, a white girl who tends to get carried away, and Dontel, a black boy who tends not to, consider motive and opportunity and work to solve the mystery even as the third-graders practice and they themselves choreograph go-go dances to be staged between each act. Griffin concocts a baroque plot involving a secret code credibly based on third-grade math and tells it with SAT-level vocabulary. She contextualizes that vocabulary carefully, sequencing sentences to prepare readers for it. Kids who understand how hard it is for Smashie and Dontel "to join a line of children who were all mad at them" will see how the "frostiness" might be "palpable." Even if Smashie and her pals don't talk like 8-year-olds, though, they behave like them, getting carried away with endearing earnestness. Griffin also subtly attacks stereotypes with her multiethnic group of hugely likable kids. Dontel's dad is a dentist, and a Latina student's mom is a patent attorney—a fact that also figures into the plot. Readers will be hoping for an equally savvy Book 3. (Mystery. 7-10)

School Library Journal (Mon Aug 01 00:00:00 CDT 2016)

Gr 3-6 Another mystery is unfolding in Room 11 at Crumpler Elementary School, and it looks like Smashie McPerter and her best friend Dontel are back to doing what they do best, investigating. Smashie is still as vivacious and dramatic as when readers last saw her, Dontel is still his incredibly patient and mature self, and the level of mystery has finally reached a fine balance between believable and exciting. The students are working on a talent show, and one of the keys to the show keeps going missing each time it is replaced. This leads to many suspects, some plausible and some far-fetched. The story is paced well, and the plot is strong enough to intrigue a variety of readers. Unfortunately, the dialogue and the vocabulary feel more appropriate to adults than to a pair of third graders. That quibble aside, the series offers positive lessons and activities that teachers and librarians can incorporate in the classroom. VERDICT The use of mathematical codes and investigative lingo and the slight mystery will make this a good book for a beginning-of-the-year read-aloud in a third or fourth grade classroom. Chad Lane, Tulip Grove Elementary School, MD