Lucretia Crocker (31 December 1829 - 9 October 1886) was an American science educator.
Crocker was born on 31 December 1829, daughter of county sheriff and businessman Henry, and Louis E. Crocker (née Farris) in Barnstable, Massachusetts. She graduated the Massachusetts State Normal School in West Newton in 1850. She attended lectures by J. L. R. Agassiz at Harvard, at the time women could only attend Harvard as guests.
She taught at the State Normal School from 1850 to 1854. From 1857 to 1859 she was professor of mathematics and astronomy at Antioch College.
In 1859 she returned to Boston to care for her parents, and become involved in educational activities there. From 1865 for some years she assisted in selecting the American Unitarian Association's Sunday School books. From 1866 to 1875 she was a member of the New England Freedman's Aid Society's Committee on Teaching.
In 1869 she toured the freedmen's schools. She was also teaching botany and mathematics in a private school at around this time.
Crocker was elected to the Boston School Committee in 1873. From 1873 to about 1876 she was head of the science department of the Society to Encourage Studies at Home, serving on the board of school supervisors from 1876 to 1886.
Crocker died on 9 October 1886 in Boston. Her home is featured on the Boston Women's Heritage Trail.