Grandstands for the opening ceremony will rise with a clatter Thursday. A number for each parade entry will be written with chalk on the road in the staging area Friday. Parking signs will be posted in early morning darkness Saturday. And when the sun comes up Saturday, April 15, the efforts of more than 550 students will climax as the University of California, Davis, hosts its 87th annual Picnic Day -- believed to be the largest student-run event in the country. "The student directors and volunteers put in hundreds of hours to make sure that every facet of the event goes smoothly," says Alex Edens, a senior from Los Altos and Picnic Day chair. "It's a long seven months." The daylong open house, expected to attract tens of thousands of people, will begin at 9:30 a.m. with opening ceremonies on the north end of the Quad, followed by a traditional parade through campus and downtown Davis. Other features will include dancing, animal events, departmental exhibits, sporting events, a children's fair and campus tours. New this year are salsa and merengue demonstrations and lessons from 3:30 p.m. to 4 p.m. at Freeborn Hall. Dancing to live salsa music will follow the lessons until 5 p.m. Popular events include: o Dachshund dog races -- 1 p.m., Recreation Hall o Chemistry Magic Show -- 10 a.m. to 2 p.m., 194 Chemistry Building o Police dog demonstrations -- 11 a.m. and 1:30 p.m., Orchard Intramural Field o Battle of the Bands -- 2 p.m., lawn at Lake Spafford o Intercollegiate athletic competitions and sporting exhibitions -- 9 a.m. to 4 p.m., all athletic fields and Hickey gym o Children's Cultural Fair -- 10 a.m. to 4 p.m., courtyard of Hart Hall A complete schedule of events and other information is available on the Picnic Day Web site at http://picnicday.ucdavis.edu/. Food, including ethnic specialties, will be available; no alcohol is allowed.