Roy P. Drachman-Agua Caliente Park, 12325 E. Roger Road, is a hotbed of activities. From 8 to 9:30 a.m. Thursdays it offers a guided walk to spot wetland birds, hummingbirds, songbirds and raptors. Binoculars are available for you to use, or bring your own. Free.
Desert Artisans’ Gallery, which is owned by local artists, is holding a one-day sidewalk art sale from 9 a.m. to 3 p.m. at 6536 E. Tanque Verde Road. Free to browse. 722-4412.
The 20th Annual Earth Day Festival is 9 a.m. to 2 p.m. at Reid Park, 900 S. Randolph Way. Attendees can sign a pledge to get a reusable bag. Pledges are entered in a raffle to win $25 gift cards from local grocery stores. Free. 322-5180.
Paintings by Joan DiGiovanni are on exhibit at the Unitarian Universalist Church of Tucson, 4831 E. 22nd St., 11:45 a.m.-1 p.m. Sundays and 9 a.m.-1 p.m. Tuesdays-Fridays through May 4. A reception will be held today at 11:45 a.m. Free. 748-1551.