On December 8, 1864, Alger became pastor of the First Unitarian Church and Society in Brewster, Massachusetts. The people of Brewster liked him. He was a good speaker. He played ball games with the boys, and took walks with them. He kept writing stories, and sent them to a boys' magazine in Boston called "Student and Schoolmate". He wrote another boys' book, "Paul Prescott's Charge". It was published in September 1865. The critics gave it good reviews.