After publishing her first novels and completing a translation of another, Sarah began to write educational texts. In the late 1750s, Sarah and Lady Barbara followed their earlier endeavors to educate poor children by writing a series of cards that concentrated on teaching history and geography. In 1761, with the accession of George III, Sarah wrote a political history about Gustav I of Sweden, "The History of Gustavus Ericson, King of Sweden"; it emphasized the concept of the "patriot king," or the selfless ruler acting for the greater good of the country. She succeeded this with "The History of Mecklenburgh" in 1762 to capitalize on the public's interest in George III's wife, Charlotte.