American writer of children's literature whose spirited writing found great success with its audience through humour, empathy, and a refusal to sermonize.

Clarke was educated at home and in the local Female Academy. In 1851 she went to Evansville, Indiana, to teach school, but growing deafness forced her to leave that position. She lived thereafter in her native town. She had written for her own amusement since childhood, but in 1861 she was invited to contribute a story to the Memphis Daily Appeal. Within a short time she was publishing stories for children regularly in Sara Jane Lippincott's Little Pilgrim magazine and in the Boston Congregationalist under the pseudonym Sophie May. Her first series of Prudy Parlin stories was collected in six volumes in 1863–65, and several such series followed, including the Dotty Dimple stories in 1867–69, the Little Prudy's Flyaway series in 1870–73, the Quinnebasset series in 1871–91, the Flaxie Frizzle stories in 1876–84, and the Little Prudy's Children series in 1894–1901.

The great popularity of Clarke's stories and books among children rested on her humour, her fidelity to the ways and thoughts of children, and her avoidance of the wooden didacticism of much of the literature intended for young readers of that day. The everyday details of village life were the material from which she constructed her moral yet lively tales, and her native village and its people, particularly her own nieces and nephews, were her models. Her few books written for adults were not successful.