There will be a whole lot going on at the Philadelphia Fall Arts Fest at the Kimmel Center for the Performing Arts. Try to keep up: Some 50 cultural organizations will strut their stuff in a day of arts, painting, Hula hooping, and live performances featuring jazz, opera, classical music, and ballet. Your Philadelphia Orchestra, led by Assistant Conductor Austin Chanu, will perform works by Leonard Bernstein, Florence Price, and Pyotr Tchaikovsky. See the solo debut by Associate Principal Bassist Gabriel Polinsky in selections from Sergei Koussevitzky’s Double Bass Concerto. An innovative, ergonomically-designed Maene-Viñoly Concert Grand Piano paying tribute to the late musician-architect l Rafael Viñoly will be on display in the Kimmel Center, where it was designed. Meet and mingle with arts organizations and see performances on the Commonwealth Plaza stage and inside the Perelman Theater by PHILADANCO!, Broadway’s WICKED, Philadelphia Ballet, Opera Philadelphia, the No Name Pops, Philadelphia Heritage Chorale, BalletX, Koren Arts & Culture, Hip Hop Fundamentals, Curtis Institute of Music, and more. Check out the kids’ paint station inspired by the upcoming costume displays from Cirque Dreams Holidaze, and a pop-up panel discussion with Opera Philadelphia, Marian Anderson Historical Society, and Harriet’s Bookshop. Explore playing various instruments at “Keep Music Alive.” Free, 11 a.m. EST to 3 p.m. EST. Most activities are in Kimmel’s Commonwealth Plaza; Your Philadelphia Orchestra will perform in Verizon Hall at 3:30 p.m. EST. Kimmel Center for the Performing Arts, 300 S. Broad St. The Orchestra’s performance is free, but tickets are based on a first-come basis onsite. 215-790-5800 or ensembleartsphilly.org.