Susan Hill 
The Boy Who Taught The Beekeeper To Read (Storycuts) 

Beekeeper and odd job man Mart May is befriended by a curious and lonely boy whilst tending to errands around the prestigious home of Lady Burnett. As the two begin to bond, the boy, James, discovers the secret of Mart”s illiteracy and – startled and concerned – takes on the task of teaching his reluctant subject to read and write. Yet when the summer holidays end, the isolated world in which the characters have grown close is broken by a return to the normality of routine and convention.
Part of the Storycuts series, this short story was previously published in the collection The Boy Who Taught the Beekeeper to Read.