"I think they're really dynamite," says saxophonist Carl Grubbs of the Voices of Independent Living, a vocal trio that grew out of a joint workshop effort of the D.C. Center for Independent Living and District Curators. Grubbs' jazz quartet will accompany the trio in performance at 3:30 p.m. today, on the main stage of Add Arts '85, a 12-hour celebration of the arts scene in Washington, commencing at noon at Gallery Place and its vicinity.

The modern jazz dance of Roberta Rothstein and troupe; Kim Jordan and Top Flight's message songs; and the dance-theater improvisation of Michelle Ava and Jack Guidone are among the afternoon offerings. The evening's program will feature saxophonist Julius Hemphill and the D.C. Jazz Workshop Orchestra, the new wave rock sounds of On Beyond Zebra, and Sweet Honey in the Rock, an a cappella vocal quartet.

On the literary arts stage at Library Place mall poets Essex Hemphill, Garth Tate and Michelle Parkerson will recite; the Source Theatre company will offer excerpts from "Back Stop!" and Cole Porter's music will be featured.. For children, there is a noon showing of "The Red Balloon," and other films, at Martin Luther King Memorial Library. The film series will continue there with the 1943 "Stormy Weather" with Lena Horne and Fats Waller, the work of some D.C. filmmakers and an 8:30 p.m. outdoor screening of "The Brother From Another Planet."

A chalk-drawing contest for youngsters, hosted by Artists' Alley; a bring-your-own-instrument jam at d.c. space; and a Vendors' Mall are some other things going on today at this year's Activities for Downtown Development in the Arts. All events are free. Rain date is tomorrow at the Mainstage at Eighth and F streets NW.