[6] In 1741 he was still apprenticed to Gustavus Hesselius[7] (1682–1755), a Swedish-born painter who resided in Philadelphia.
[8] He had two early students that went on to become well known artists: James Claypoole, Jr. (ca 1743–1822), and Matthew Pratt (1734–1805).
Commissioned and paid $8 by Captain Abram Markoe in 1775 to paint a flag[9] for the Philadelphia Troop of Light Horse.
He had three children from this marriage: After Rebecca's death on July 19, 1749[11] he married Mary Chambers (d. 1796)[12] in September 1750[13] and had nine children with her: He was father-in-law to both the miniature portraitist James Peale and Col. Timothy Matlack (1730–1829), a Free Quaker, merchant, surveyor, architect, statesman, and patriot in the American Revolution.
A portrait of James Claypoole Sr. by James Peale and/or Charles Willson Peale is in the Pennsylvania Academy of the Fine Arts, Philadelphia, Pennsylvania.