As "The School Book" opens, the faculty and board of Tigris, a Cambridge, Mass., private school, gather for a cocktail party to celebrate the arrival of Valerie Green, their new headmistress. It's a stiff-upper-lip gathering: The weather is unseasonably cold, and the guests suffer, but no one is brave enough to suggest that they move indoors. That would be letting Tigris School down.

Anne Bernays knows the rarefield private-school world well; she moves deftly through school hallways and board meeting in this novel, attending to students, faculty and even that terrifying specter, the headmistress' secretary. Her narrator, Sally Cooper, is a newcomer to the Tigris faculty, and so has a relatively objective eye. She makes a shrewd observer of the folkways of the school and its inhabitants. But she discovers, sometimes to her own loss, that schools have a way of taking over one's life.

Tigris prides itself on attending to the individual student -- even to his soul. The school is meant to be -- like that river in the Fertile Crescent we all learned about in the third grade -- a life-giving force. The comic possibilities within such an institution are many, and Bernays realizes many of them. She has a sure ear for the adolescent voice and a good eye for children's posturings.

Sally Cooper watches a class straggle in to chorus rehearsal, looking "as if they thought they were the coolest kids on earth. It wouldn't have surprised me to see one of them pull out a joint, light it, and pass it around."

Tigris students are a hardened lot; during the year before the novel takes place, they had to weather "a rape, a near fatal explosion, and a hunger strike." Valerie Green has been brought in to pull the faltering school back together. She's the right type, one we all recognize:

"Valerie was tall and large-boned. I figured a size nine shoe. She looked Seven Sisters. . . She wore low-heeled blue suede sandals and an unnecessary belt that emphasized bulk rather than thinness. She had vigorous eyes, a longish nose with large expressive nostrils, a full mobile mouth and the posture of someone who had been constantly reminded as a child to sit up straight."

A formidable lady. And she does a bang-up job with the languishing Tigris faculty, shaking up the curriculum, exciting the student body with her leadership. But she also, unfortunately, falls for the art teacher and her indiscretions are observed by some of the students. Their headmistress' behavior is too much even for Tigris School sophisticates.

"The School Book" tells a relatively simple story, but in the double hot-house of Cambridge and Tigris, events are blown far beyond their proportions. Valeie Green makes some political errors -- for instance, allowing a reporter doing an investigative story on private schools onto the campus -- but she compounds them when she falls in love. Perhaps not the ingredients of grand opera, but within the confines of a few parental living rooms, such events can become high drama, and high comedy.

Much of "The School Book" is taken up with the troubles Sally Cooper lives through as Tigris goes through its difficult year. She's a poor little girl, divorced, a flutist. She lives in a wonderful house, where the few valuable paintings her father didn't will to the MFA are hung. Her life is filled with memories of an awful husband, and with her music. She's an attractive character, although we sometimes wish that she -- and Bernays -- would get back to Tigris School, because that is where Bernays is at her best, and funniest. There are lovely moments: a student chides a visiting photographer for littering; another student sells space at the window of the shed where Valerie Green carries on his liaison.

Most interesting -- and truest -- are those moments that focus on "this troubled year [that] absorbed the Tigris community as if it were the only organism on the entire planet." Because, of course, that's what being in a school is really like.