Life on Martha’s Vineyard has been mostly ideal for 11-year-old Mary Elizabeth Lambert, the protagonist of Ann Clare LeZotte’s historical novel SHOW ME A SIGN (Scholastic, 288 pp., $18.99; ages 8 to 12).

It’s 1805 and she’s lived in Chilmark her whole life, unaware of the safe harbor it has provided from the outside world.

Mary and her fellow Chilmark residents are descendants of English colonists such as her great-great-grandfather Jonathan Lambert, who arrived in 1692 from the Weald, a region in Kent known for its deaf population. Over time, as the townspeople have become a mix of the hearing and the deaf, they’ve replaced Lambert’s English sign language with their own homegrown version.

This community seems to embrace intersectional identities. Mary, who is deaf, enjoys amateur spy expeditions with her best friend, Nancy Skiffe — who was born hearing to deaf parents — and exchanges stories with the grizzled hermit Ezra Brewer. She trails after Thomas Richards, a freed former slave working as a farmhand for her father, or his daughter, Sally, who is Wampanoag Indian on her mother’s side.

But the islanders coexist at the edge of discord. Freedmen, like Thomas, aren’t invited into Mary’s home; he could be kidnapped and sold back into slavery at any time. Irish immigrants are only slightly more accepted. Colonists, like Nancy’s father, angrily lay claim to lands that the Wampanoag have lived on for generations.

Amid such tensions among the people she loves, Mary has one overriding concern. It has been eight months since her beloved brother, George, was killed in a carriage accident as they played on the high road. Pushed out of harm’s way by George, Mary has been guiltily concealing the fact that she was the one who suggested their outing.

Will her parents ever forgive her if they find out the truth?

Meanwhile, news spreads of an unexpected visitor — a guest of the local reverend. He is Andrew Noble, a young scientist from Yale interested in studying the town’s unusually high number of deaf people.

Noble is warmly welcomed at first, but he soon reveals a troubling attitude: As a man of the Enlightenment, he says his aim is to find the source of the islanders’ “infirmity,” to use facts and data to unlock the “disease” that has stricken one in four Chilmark residents.

His views are a stark and insulting contrast to the villagers’ self-concept.

“Papa was right,” Mary tells herself. “We are fine as we were made.”

Using her spying talents, Mary quickly discovers not only that Noble has come in search of “a live specimen” to examine, but also the chilling reality of what that entails.

Yet LeZotte’s novel is more than just a page-turner. Well researched and spare, it’s a sensitive portrayal of a young girl’s fight for respect and human dignity.

LeZotte, deaf herself, has created a fully realized cast of characters, led by a protagonist whose mind and heart are in perfect sync.

“The way my mind thinks is not just in signs or English words and sentences,” Mary observes, “but in images and a flow of feeling that I imagine resembles the music I’ve never heard.”

Dialogue, both spoken and signed, is handled deftly, showing the rich cadences and patterns of each form of expression. LeZotte also gives readers a sense of M.V.S.L. (Martha’s Vineyard Sign Language), a combination of “home sign” and American Sign Language used by the islanders through the mid-1900s.

Like Laurie Halse Anderson’s “Seeds of America” trilogy, this work of historical fiction offers a fresh perspective on the post-Revolutionary War years by exploring issues that are just as relevant today.

Middle-grade readers of every age will find a girl to root for who is asking all the right questions as she grows: Who determines a person’s value? By what means does a community decide what is right and fair? How do we move forward from injustices of the past?