Participate in the 2004 Great American Cleanup Saturday, April 24 from 9 a.m. to noon. The cleanup is sponsored by Keep Greater Milwaukee Beautiful, Inc. Go to www.kgmb.org for information and to download a registration form. Can’t do it on this day and want to organize your own neighborhood cleanup? Contact KGMB at 414/272-5462. . . . . . . . . . . . . . . . . . . . The Urban Ecology Center is seeking equipment donations to fill their new building in Riverside Park. They are looking for clean, quality items, and equipment that works. In some cases they can only buy new and would welcome targeted purchases (see UrbanEcologyCenter.org for this list). The center has storage available and can arrange pickups. If you have something to donate, please contact Vince Bushell at 265-7278 or . The third annual Earth Day Celebration and River Revitalization Foundation benefit will be held Thursday, April 22, from 5-9 p.m. at the Gordon Park Pavilion at the corner of Humboldt Boulevard and Locust Street. Your $10 cover will help support Beerline Trail, which starts at the south end of Gordon Park. . . . . . . . . . . . . . . . . . . . Join the Sierra Club Great Waters Group April 19 to hear about Pam Flowers’ solo journey across the Arctic, 7 p.m. at the group’s monthly meeting at the Mayfair Mall Community Room. Flowers is the first woman and first American to make this trek. She encountered polar bears, bitter cold, isolation, and winter storms, but finished the adventure with her team of dogs safe and sound. She will share her slides and stories, including pictures of the Arctic National Wildlife Refuge. For more info visit www.wisconsin.sierraclub.org/gwg/.