Farnsworth attended public schools in New Orleans, Louisiana; Savannah, Georgia; and New York. In 1916, while serving in the U. S. Navy and stationed in Washington, D. C., he studied nights at the Corcoran Gallery of Art school, and in Provincetown in 1921 he studied with Charles Hawthorne. Farnsworth and Helen Alton Sawyer, also a Hawthorne student, married in 1925.
In his practice as a painter Farnsworth was noted for his versatility. Although primarily a portraitist, he was also prolific in his output of studio-posed figure studies, still lifes, and to a lesser extent, landscapes. He achieved perhaps greater fame as a popular and energetic teacher. In New York he taught at the Art Students League and at the Grand Central Art School, however, it was with his own schools, where he perpetuated Hawthorne's methods, that he was most active as an instructor. After 1933 he held a summer school in North Truro, Massachusetts, near Provincetown, and after 1935 taught winters in Sarasota, Florida. His instructional books, Painting With Jerry Farnsworth, published in 1949, and Learning To Paint In Oil, 1957, were immensely popular and contributed to his being a nationally known figure.
A frequent participant in Academy exhibitions, Farnsworth received Hallgarten prizes in the annual exhibitions of 1925 and 1927; the Clarke Prize in 1933; the Proctor Prize in 1935; the Isidor Medal in 1936; an Altman prize in 1938; and Maynard Prize in 1952. He served on the Academy Council for the year 1938-39.
Farnsworth was represented by the Grand Central Galleries, New York.
