Ride the 'T' for free day, sponsored by the Lawrence Transit System, www.lawrencetransit.org.
Life Support Rally, benefit for Headquarters Counseling Center, 7:30 a.m.-2 p.m., Sunflower School, 2521 Inverness Drive, admission for various events listed at www.lifesupportrally.org.
Fundraiser: To the River and Back, 5K/10K run, pancake feed and open house for the Lawrence Community Nursery School, race starts at 8 a.m., costs vary; www.totheriverandback.org.
Lawrence Arthritis Walk, benefit for The Arthritis Foundation, 9 a.m., Lawrence Indoor Aquatic Center, 272-8461.
MS Walk 2006, for the National Multiple Sclerosis Society, 9 a.m., Hobbs Taylor Lofts in the 700 block of New Hampshire Street; 841-0947.
Oread Neighborhood Assn. meeting, with Deon Wolfenbarger, coordinator of the National Register of Historic Places nomination, 9:30 a.m., Watkins Community Museum of History, 1047 Mass.
Caring for Your Quilts Workshop, $15, 10 a.m.-noon, Watkins Community Museum of History, 1047 Mass., 841-4109.
Earth Day special program, games and interpretive walks, 10 a.m.-noon, Prairie Park Nature Center, 2730 Harper St., for all ages.
Earth Day. 11 a.m. parade down Massachusetts Street; festival including music and food from 11:30 a.m. to 4 p.m. at South Park.
Free tennis clinic, noon- 4 p.m., First Serve, 5200 Clinton Parkway, for all ages.
Bookworms Unite!, for 8- to 12-year-olds, 2:30 p.m.-3:30 p.m., Lawrence Public Library gallery, 707 Vt., registration requested, 843-3833 ext. 117.
18th Annual KU Pow-Wow, 1 p.m. and 7 p.m., Robinson Center Gymnasium at Kansas University. Contact 864-2846.
Public ceremony: Imagination & Place Environmental Award winner announcement, 5:30 p.m., Lawrence Arts Center, 940 N.H.
Bishop Seabury Annual Benefit Auction, 6 p.m. at the school. Contact 832-1717.
Music Mentors Benefit Concert, 1 p.m.-6 p.m. at South Park, 12th and Massachusetts streets.
Immunization clinic by the Lawrence-Douglas County Health Department, 8:30 a.m.-11:30 a.m. and 1 p.m.-8 p.m., 200 Maine, 843-0721.
Douglas County Commission meeting, 8:30 a.m., county courthouse, 1100 Mass.
Medicare information, 10 a.m., studio of Lawrence Senior Center, 745 Vt., 842-0543.
Lawrence-Douglas County Housing Authority Board of Commissioners annual meeting, 5:30 p.m., Babcock Place, 1700 Mass.
Lawrence school board meeting, 7 p.m., district headquarters, 110 McDonald Drive.
Class: "Past Lives, Dreams and Soul Travel," 7 p.m.-8:30 p.m., Lawrence Memorial Hospital, Room D North, 325 Maine, free.
Eudora City Council meeting, 7:30 p.m., Eudora City Hall, 4 E. Seventh St.
Immunization clinic by Lawrence-Douglas County Health Department, 9:30 a.m.-11:30 a.m. and 1 p.m.-4:30 p.m., 200 Maine, 843-0721.
Storytime, 10:30 a.m.-11 a.m., Lawrence Public Library's Children's Room, 707 Vt., 843-3833, ext. 117.
Study group: "Politics in an Age of Entertainment & Instant Information," led by Fellow John Toohey, 4 p.m.-5:30 p.m., Dole Institute of Politics, KU's west campus, open to the public.