Nan at Camp Chicopee; or, Nan's Summer with the Boys (1896)
Nan's in the City; or, Nan's Winter with the Girls (1897)
Nan's Chicopee Children (1900)
Catharine's Proxy; A Story of Schoolgirl Life (1902)
Online at Internet Archive
Persis Putnam's Trasure; or, Nan's Girls at Camp Chicopina (1908)
The series is listed in most bibliographies as Nan, but the Library of Congress catalogue card for Nan's Chicopee
Children bears the notation "On verso of half-title: The Chicopee series, v. 3"