The seventh in a line of verse math-terpieces that began with Grapes of Math (2001), this offers 16 problem-solving shortcuts that involve grouping numbers or items. Tang not only provides answers and methods in a closing key, he is generous with hints. Opposite digitally worked, color-coded arrays of anywhere from 30 to 148 stars, sea shells, spiders, pickles, the titular potatoes, playing cards and the like, his verses open with a pair of lively introductory couplets, set the problem with a third, then suggest an approach in the fourth: “Can you add up these poor souls / For whom the bell already tolls? / In groups of ten you’ll hear their cries, / ‘Please don’t turn us into fries!’ ” Even numerically challenged readers can count on coming away with some time and labor saving techniques for toting things up. (Picture book/nonfiction. 7-9)
