The Triplet Threat (Math Mysteries #1)

Numbers are the key to rooting out the truth in this low-stakes first installment of an arithmetic whodunit series by Starmer (A Million Views). Abby Feldstein, Cam McGill, and Gabe Kim call themselves the Prime Detectives, so named for their reputation as sleuths who use math to solve mysteries and for their friendship, which is as indivisible as prime numbers. The first day of fourth grade immediately tests the trio’s mettle: the Penderton triplets, three brothers new to Arithmos Elementary, bustle into the classroom expecting to be early but are instead inexplicably 10 minutes tardy. In this first of several episodic numerical capers, the Prime Detectives crack the case, detailing via concise prose how they use mathematical logic to puzzle out those missing minutes. The team breaks subsequent mysteries down into digestible math problems, using conversions to explain a batch of inedible cookies and statistics to demonstrate how a gym class obstacle course went sideways. Cheerful, limited blue-palette illustrations by Kissi (the Wind Riders series) accompany each adventure, making for a fast-reading story that’s light on mystery but rich in equations. Characters are depicted as having varying skin tones. Ages 8–11. Agent: Michael Bourret, Dystel, Goderich & Bourret. (Aug.)