ALA Booklist (Wed Apr 01 00:00:00 CDT 2020)

In this particularly silly transitional chapter book, Professor Albert Hopper and his niece and nephew, Polly and Tad, tunnel to the center of the earth in a massive caterpillar-shaped metal ship. Plans quickly go awry when Hopper uses a double negative, telling Tad he "must not NOT press" the A-C-H (Anything Can Happen) button that he installed in the ship "just in case." Thanks to the ACH, the trio meet living cave frogs, are chased by a T. rex fossil, and meet yeti on the top of Mt. Everest. Facts about the Earth's layers are woven into the story and summarized at the end in "Polly's Notes." The characters are standard issue: cautious Tad, book-smart Polly, quirky Uncle Hopper. Amusing dialogue provides genuinely funny moments, as do the times when the characters break the fourth wall. The plot muddles a bit when they accidentally pierce the ocean floor and escape into a magma tunnel, but clips along overall. Large text and plentiful illustrations, accented with green, make this a solid choice for readers moving into chapter books.

Kirkus Reviews (Wed Apr 01 00:00:00 CDT 2020)

A ground-shaking, pulse-pounding journey to the Earth's core and back (with a few side trips along the way).In typically grandiloquent tones-"We shall be…WORMING TO the CENTER OF THE EARTH!"-froggy explorer Albert Hopper invites Junior Science Heroes (and niece and nephew) Polly and Tad on a voyage of danger and discovery aboard aptly named mechanical drill Wiggles. Though Tad's inability to leave the onboard "Anything Can Happen" button alone results in time travel, an encounter with prehistoric cavefrogs ("We shall explore this…UNEXPLORED CAVERN!"), and other unexpected twists, the trip also features plenty of basic natural science. The travelers go from crustal plates to core ("The inner core is nearly…TEN THOUSAND DEGREES!"), up and down a volcano's lava tubes, and through an earthquake. Meanwhile Hopper or know-it-all Polly discourse on topics geological, from plate tectonics and the three types of rocks to cratons. Thick-lined cartoon vignettes with green highlights on nearly every page capture the comical turns better than they do the science, but along with tucking in the occasional rudimentary chart or poster, Himmelman backs up the factual content with summary notes from both Junior Science Heroes at the end. For an equally rousing but visually richer dive into the depths, follow up with Jon Chad's Leo Geo and His Miraculous Journey Through the Center of the Earth (2012).Will leave readers eager to…GO AGAIN! (Informational fantasy. 7-10)

School Library Journal (Wed Apr 01 00:00:00 CDT 2020)

Gr 1-3 Albert Hopper is on a mission to travel to the center of the Earth. In his carefully crafted worm-like ship, Wiggles, Albert is joined by his niece and nephew as they encounter extreme temperatures, magnetism, and other unexpected conditions. Of course, nothing goes as planned. The premise of this book is fun and has potential, but the execution misses the mark. Young readers will learn about the different layers of the Earth but given the short length of the book, many details are left out. This skimming of the scientific components leaves many unanswered questions, and details of the story are unexplained. This book could be paired with a science program about the layers of the Earth to fill in some of the information gaps. The black-and-white illustrations are simple with green accents (and green frogs) and don't do much to advance the story. They do break up the text, making the book more accessible for younger readers. VERDICT An additional purchase for larger libraries looking to expand their early chapter book sections. Jessica Trafton, Skidompha Library, Damariscotta, ME