Her novels include:
* The Wonderful Winter (1940)
* The Long Dive (1941)
* Mountain Pony (1942)
* Match Point (1943)
* High Meadow (1945)
* The Moon is a Crystal Ball (1946)
* The Hole in the Wall (1948)
* Big River to Adventure (1949)
* Song for a Lute (1950)
* The Story of America's First National Monument (1951)
* The Land is Always Green (1953)
* A Horse on the Mountain (1955)
* High as a Kite (1958)
* Firefly Summer (1959)
* The First Book of American History (1961)
* The First Book of Presidents (1962)
* The First Book of Space Travel (1962)
* Time for Tammie (1963)
* The Fast Sooner Hound (1964)
* The Story of the Ice Age (1965)
* The First Book of Elections (1966)
* The Story of the First World War (1967)
* The Story of the Second World War (1968)
* The First Book of Codes and Ciphers (1969)
* The Story of Colonial America (1970)
* The Story of the Old West (1971)
* The Story of the Civil War (1972)
* The First Book of Maps and Globes (1973)
* The Story of the Revolutionary War (1974)
* The First Book of the Thirteen Colonies (1975)
* The First Book of Time (1976)
* The Story of Reconstruction (1977)
* The First Book of Money (1978)
* The First Book of Photography (1979)
* The First Book of the Constitution (1980)
* The Story of American Industry (1981)
* The Story of American Education (1982)
* The Story of American Literature (1983)
* The Story of American Music (1984)
* The Story of American Art (1985)
* The Story of American Invention (1986)
* The Story of American Transportation (1987)
* The Story of American Sports (1988)
* The Story of American Medicine (1989)
* The Story of American Science (1990)
* The Story of American Exploration (1991)
* The Story of American Women (1992)
* The Story of American Civil Rights (1993)
* The Story of American Popular Culture (1994)
In addition, she wrote several short stories and articles for magazines and newspapers.