Return to the Summer Stacks 2nd – 3rd for Ithan

It’s the first day of the fourth grade at Arthimos Elementary and things are already off to a strange start—poisonous cookies, a zipline disaster, a missing iPad, and what are those strange sounds coming from the school custodian’s wheelbarrow? Luckily the Prime Detectives—Abby “the Abacus” Feldstein, Cameron “Cam” McGill, and Gabriel “Gabe” Kim—are on the case! Using arithmetic, geometry, and logic, the Prime Detectives are sure to figure out who did what, when, and why! A gripping new middle-grade mystery series, each book contains multiple, interlinked mysteries that readers help solve using math. Includes answers showing step-by-step solutions.