When 12-year-old Ava Anderson finds a magic pencil in the kitchen junk drawer, geometry becomes a lot easier—and her life becomes much more complicated.
Ava lives with her family in upstate New York, along with two goats purchased by her father in hopes that fresh goats' milk will help Anderson's General Store survive the new Shop-Mart superstore. Ava is afraid of the goats. She's also afraid of math tests, band audition, field trips and participating in the lunchtime library book club at school. So when her pencil says, "Two Pi R," when she desperately writes, "What is the formula to find the circumference of a circle?" on her math test, she sees her road to certainty. But it won't answer just any question—like whether her parents may get divorced—as people have free will, and some answers are just plain terrifying, like whether her grandmother is going to die. Messner plunges Ava into recognizable preteen situations both at school and at home. She stuffs her book with issues, though, and both the nature of and the explanation for the pencil's magic are fatally contrived. Nevertheless, readers will cheer as Ava heroically tackles a terrifying ropes course alone so that her mother will get a medical test only Ava knows she needs.
This sympathetic protagonist offers children a mostly successful look at clinical anxiety. (Fantasy. 8-12)