Jackie's athleticism was balanced by an artistic, creative side. Drawn to poetry and literature, she learned to read at a young age, and by the age of five she could recite memorized passages from The Wonderful Wizard of Oz and Little Lord Fauntleroy. Although Jackie frequently closed off emotionally and refrained from talking about her deepest feelings concerning her parents' difficult relationship and, later, divorce, she found release by expressing herself through writing verses and stories. Her first poems and stories were for her family, but as she got older she wrote for friends and classmates. She often illustrated her writing with hand-drawn pictures. As a teenager in boarding school she wrote articles for the school newspaper, Salmagundy. The paper also published cartoons she submitted about a character called Frenzied Frieda whose exploits regularly got her in trouble — not unlike Jackie, who still managed to rankle teachers with her mischievousness.

Her ability to draw led Jackie to start painting. She would create canvases for Christmas gifts and once wryly noted that they were decent enough that her mother would leave them up for a full month after the holidays were over before stashing them in a closet. Grampy Jack exposed Jackie to art as a young child, and as she got older she formally studied art history and was well versed in classic styles and artists.

One of Jackie's deepest passions was for live performance, be it music or dance. She was particularly enchanted by ballet. She took lessons as a little girl and quickly realized she only had average talent. But she never lost interest and eagerly devoured any book on the subject.

Jackie also enjoyed theater and in high school wrote a musical that was produced by the drama club. She admitted to her stepbrother Yusha Auchincloss that she would have loved to have been an actress but acknowledged she would never be willing to be a struggling, starving artist. She showed glimpses of her potential as a talented mimic, however, and entertained her classmates with impressions of teachers. Her natural ear also made learning new languages easy for Jackie. Janet had made sure that her daughters learned to speak French by insisting it be the only language allowed at the dinner table. Later, Jackie also became fluent in Spanish and Italian.