This year's recipients of the nation's two most prestigious children's-book awards were announced by the Association for Library Service to Children during the American Library Association meeting in January. The John Newbery Award for most distinguished text went to author Patricia MacLachlan for her book ``Sarah, Plain and Tall.'' The story, based on a true incident from Miss MacLachlan's family history, is about the uncertainty and excitement surrounding the arrival of Sarah, who has agreed to try life on a pioneer homestead in answer to a widower's ad for a wife and a mother.
The Randolph Caldecott Medal for the most distinguished American picture book was awarded to artist Chris Van Allsburg for ``The Polar Express.'' Mr. Van Allsburg's oil pastels create a haunting atmosphere for a story about a small boy who longs to believe in the magic of Christmas and the North Pole. In 1982 Van Allsburg won the Caldecott Medal for ``Jumanji,'' and his ``Garden of Abdul Gasazi'' was a Caldecott honor book in 1980.
The Newbery honor books for 1986 are ``Commodore Perry in the Land of the Shogun,'' by Rhoda Blumberg, and ``Dogsong,'' by Gary Paulsen.
The two Caldecott honor books are ``The Relatives Came,'' illustrated by Stephen Gammell and written by Cynthia Rylant, and ``King Bidgood's in the Bathtub,'' by Audrey Wood and illustrated by Don Wood.