Jella Lehman, born in Stuttgart, was the oldest daughter of the manufacturer Josef Lehmann (1853-1911) and his wife Flora born Lauchheimer (1867-1940). The parental home belonged to the Jewish-liberal Judaism. After the school days at the Königin-Katharina-Stift-Gymnasium Stuttgart she spent a year in a Swiss pension.
After her return to Stuttgart, she married Gustav Horace Lepman (1877-1922), the son of a German-born American and member of a bed-feather factory in Feuerbach. Two children emerged from the marriage (Anne-Marie, born in 1918, Günther, born in 1921). Gustav Lepman fought during the First World War as a German officer in France. He survived the First World War, but died in 1922 from his injuries of war.
After the death of her husband, Jella Lepman became editor of the Stuttgarter Neues Tagblatt, the first woman ever in this position. She wrote socio-political contributions and established "The woman in house, profession and society", in 1927. In addition, she published her first children's book (1927 The Sleeping Sunday) and a theatrical play for children (1929 The Singing Pfennig). She became a member of the German Democratic Party (Deutsche Demokratische Partei, DDP), where she was a leader in the women's group. In 1929, she ran, unsuccessfully, for the German Reichstag.
With the Nazi seizure of power in 1933, Jella Lepman, as a Jew, lost her permanent position. Until 1935 she was still employed as a freelancer. In 1936, she emigrated with her two children through Italy to England. There, she took on journalistic and literary work. In 1938 she took on the estate of Arthur Schnitzler at the University of Cambridge. Later, she worked for the BBC and the American Broadcasting Station in Europe (ABSIE). In 1943 she published the book Women in Nazi Germany under the pseudonym Katherine Thomas.
After the end of World War II, in 1945 she returned to Germany, as a consultant to the US Army for women and youth questions within the Reeducation program of the American occupied zone, where she lived first in Bad Homburg vor der Höhe, then in Munich. After the establishment of the International Youth Library, she was director there until her retirement in 1957.
During the reconstruction of Germany, she was convinced that the hope should be placed into the hands of the children and that the best medium to achieve this was through books. Her work was mainly focused on the promotion of children's and youth literature and being able to teach them open-mindedness, tolerance and pacifism. In 1946, working with the International Youth book exhibition, she held the first international exhibition in Germany after the war. The exhibition surrounded itself around the International Youth Library which opened on 14 September 1949. In 1952 she initiated a conference about international understanding through children's books, on which the International Board on Books for Young People in based. Lepman wrote more in detail about this time of her life in her autobiographical book Die Kinderbuchbrücke.
Jella Lepman wrote many children’s books and collections of children’s stories, including a large multivolume collection of bedtime stories that she collected over the years, which have been translated into many different languages. In addition to her own children's books she suggested Erich Kästner and his picture book Die Konferenz der Tiere.
She was one of the initiators of the 1956 created Hans Christian Andersen Award, the world's most important award for young people's literature.
Lepman died in 1970 at the age of 79 years in Zurich and her final resting place is in the Zurich Enzenbühl cemetery on Forchstraße.
Since 1991, in honor of Lepman's 100th birthday, the International Board on Books for Young People awards the "Jella-Lepman Medal" to people who have made a difference in the institution.Der verschlafene Sonntag (1927)
Wer ist Lux? Eine Detektivgeschichte für die Jugend (1950)
Das Geheimnis vom Kuckuckshof - Eine Detektivgeschichte aus dem Schwarzwald (1958)
Die Katze mit der Brille - Die schönsten Gutenachtgeschichten (1959)
Die Kinderbuchbrücke (1964)
Kinder sehen unsere Welt - Texte und Zeichnungen aus 35 Ländern (1970)
Der verhaftete Papagei, Ullstein Taschenbuch, Berlin 1981, ISBN 3-548-00534-9
1957 Order of Merit of the Federal Republic of Germany
1960 Goethe Medal