Continuing her lightweight alphabet of portraits of kids just entering their teens (A, My Name is Ami, 1987), Mazer introduces the series' first boy. Cal Miller and his divorced mother, Nina, live with Garo and his widowed dad, Alan; brisk and independent, Nina is professional about her role as housekeeper, though, to Garo, she's his only parent during pilot Alan's frequent absences. The boys, both in seventh grade, are close friends and bicker like brothers; Cal is genuinely modest about (and even oblivious to) his superior talents, but sometimes feels that Garo is an unwelcome rival for Nina's attention. Cal's even more preoccupied with the father from whom he's had just three postcards in seven years; the story's denouement involves the feckless Mr. Miller's reappearance and Cal's forging a tentative link with him, recognizing their similarities despite Dad's obvious faults (he's unreliable and improvident). Easily read, but far from shallow. With deftly sketched glimpses, Mazer hints that these are all fully dimensional characters; and, while each evolves to a new level, both the Millers' status in the household and Cal's relationship with his dad are left realistically open-ended. Mazer's skill in telling the reader more about Cal than he knows about himself, while narrating in Cal's unique, taciturn voice, is especially memorable. Undemanding but nourishing.