WASHINGTON (AP) — The Kennedy Center for the Performing Arts is planning its first major expansion since it opened in 1971 as the nation's "living memorial" to President John F. Kennedy.

The center is unveiling plans Tuesday for a $100 million addition. It would include pavilions to house rehearsal halls and classrooms, a memorial garden and a stage floating on the Potomac River's edge for outdoor performances. Architect Steven Holl is designing the expansion.

Officials plan to raise private funds to build the project. To kick off the capital campaign, Kennedy Center Chairman David Rubenstein is giving $50 million to fund half the cost.

Kennedy Center leaders say they desperately need space for rehearsals and education programs, especially after taking on the Washington National Opera as an affiliate.