The Marilyn Sippy papers date from 1955 to 2016 and measure 10 linear inches. The papers are arranged in seven series: Biographical information, Peace movement, United Nations (UN), Elizabeth Young, Campfire Girls, Correspondence, and Artifacts.

The Biographical Information series (1995-2004) contains a biographical information sheet written by Sippy, two brochures on organizations assisting children with mental and intellectual disabilities, and a chapter about Sippy's volunteering from America's Small Town Heroes, by Harold William Thorpe, 2003.

Sippy's involvement in grassroots peace work is reflected in the Peace Movement series (1955-1965). The series consists of Sippy's printed material and correspondence with publishers both requesting and applauding the publication of articles that dealt with peace and nuclear test bans.

The United Nations series (1968-2004) consists of United Nations Association of Iowa (UNA) newsletters and correspondence, and UNICEF financial reports, printed material, and game sheets used for Trick or Treat collections. Newspaper clippings include articles concerning the UNICEF organization, collection announcements, and letters to the editor. Sippy's recollections of her work as the Marion Area Chairman complete the series.

The Elizabeth Young series (1979-1996) contains papers relating to fellow peace activist and volunteer Elizabeth Young. Young (1910-1999), a resident of Cedar Rapids, Iowa since 1948, was born and raised in San Francisco, California. Married to James Young in 1938, the couple raised two children, David and Eve. Elizabeth Young, a journalist, editor and short story writer, held bachelor's and master's degrees in English Literature from Stanford University and later pursued a bachelor's degree in music from Coe College in 1962. She then turned her attention to a career in acting during the 1970s. An active member of the peace movement, Young was a member of the United Nations Association and volunteer on the UNICEF Card and Gift Committee. The series contains a holiday letter written by Young to her friends and family after the death of her husband, and Elizabeth Young's memorial service program. Included are newspaper clippings pertaining to Young's theatre career and articles she wrote for the Cedar Rapids Gazette's "Outlooks" column.

The Campfire Girls series (1958-1978) contains a background note written by Sippy about her involvement with the organization. The national organization was formed in 1910, and aimed to teach girls good health, self-reliance, and independence. The Iowana Council was formed in 1912; the organization has since disbanded. In 1973, the administration updated the program to discourage passivity, docility, and dependence. The series consists of printed materials and includes numerous songs, crafts, and games, as well as a menu for the Marion Cookout. The materials provide a glimpse of girlhood during a time of social change.

The Correspondence series (1979-2007) contains letters to Sippy from Marion Carson, and postcards from Carson to Joyce Maxey Conley. The series also includes information about Carson and a newspaper clipping about Joyce Maxey (later Conley). Carson and Sippy were acquainted through various peace efforts, and were both involved with the People’s Church of Cedar Rapids, Iowa. Though the two lived less than a mile apart, they maintained a robust correspondence for years. Marilyn Sippy would hand-deliver her notes to Marion Carson’s mail drop, a process that Carson fondly called “Elf Mail.” Their correspondence is notable for numerous frank conversations about aging and death. Postcards from Carson have been filed with her other correspondence, as many of the letters and postcards refer to each other. Joyce Thayer Maxey Conley (nee Kinsman) traveled internationally presenting her research about twins. Working with Dr. Warner Kloepfer, Tulane University, she developed a handprint/footprint instruction kit to be used in his studies of twins.

The Artifacts series is comprised of UNICEF school supplies which were given to children as prizes, and a Trick or Treat Collection Box.