In a season where the farm and small town are providing some remarkable looks at human fate, "Words by Heart," the story of a family of black sharecroppers in turn-of-the century Missouri, adds a notable chapter.

"Words," which will begin on WETA (Channel 26) and Maryland Public Television stations tonight at 8 p.m. and conclude next Monday at 8, teems with respectable credits. The cast stars Robert Hooks, Charlotte Rae and Alfre Woodard, and they are a funny and mesmerizing trio. The story is based on a 1979 novel by Ouida Sebestyen, which won a string of accolades and awards, including the Library of Congress' Children's Book of the Year.

The outstanding praise and the impeccable cast should be an intellectual seducer, not a turnoff. You might expect a too-good-to-be-true morality play, and "Words" does squeak of good intentions. But here what is important is the fine delivery of a good idea: the acting is seamless, the settings are authentic, and the dialogue, adapted by Frank Dandridge, might be too ideal at times, but it sings.

"Words," like many prairie pictures, is a complicated canvas of emotions, mores and personal challenges. The story of prejudice on the frontier is an often ignored one. The title at first appears to have only one meaning, taken from an early scene where the town's youngsters have a memorizing contest.

Lena Sills, the daughter of the only black family in town, wins the contest, to the shock and chagrin of the white students and their parents. In fact, the ribboned prize turns out to be a bow tie, which the officials thought would naturally go to a white classmate. Disappointed but also rightfully disgusted, young Sills throws the prize back to the officials and starts her symbolic responsibility in the story as the questioner. Fran Robinson brings a sparkling maturity to the role of Lena.

The Sills family lives on the property of Mary Chism, a rich widow played by Rae. Completing the main cast are the Haneys, a large white family also working for Chism. Ben Sills, played robustly by Hooks, climbs steadily in Chism's eyes by working hard. Little by little she gives some of Charlie and Tater Haney's responsibilities to Sills. And that sparks the wounded pride and active prejudice that lead to the dramatic conflicts.

Everywhere this cast turns it has to reexamine an idea. After the contest, Lena Sills has to think about self-respect. Her father tells her: "Rewards don't prove you are somebody. When you are somebody inside yourself, you don't have to be told." He has to alter his optimism and stop shielding his children from realities of racism. In the hands of Woodard, Claudie Sills is a woman who learns black people can edge white people to change with deeds and words. The Haneys have to learn that black people are real, not objects or simple spoilers of the status quo.

In this drama, Rae gives her "Facts of Life" sitcom fans enough chuckling to be familiar but also brings depth to the role of overlord and kook to gain new followers. In all her scenes, Woodard brings electricity and now, despite her fine comic roles, she can be considered the owner of Cicely Tyson's old title of black tragedienne.

At the end, the "Words" in the title also means the experiences Lena Sills gains from books, the link the books provide between her and a white classmate, and the philosophy of love and forgiveness that Ben Sills espouses and that changes all their relationships. In its lyric but tragic unfolding, the lessons of "Words" are a worthwhile investment.