Now in its fourth year, Smithsonian's National Zoo presents ZooLights, in which colorful Christmas lights illuminate life-sized animal silhouettes, dancing trees, buildings and walkways. All that, plus select animal houses will be open, displaying nocturnal creatures, including the Small Mammal House, the Great Ape House and Reptile Discover Center. A canned food drive benefits D.C. Central Kitchen. Now through Thursday, Dec. 23. Also, Sunday, Dec. 26, through Thursday, Dec. 30, and Saturday, Jan. 1, from 6 p.m. to 8:30 p.m. National Zoo, 3001 Connecticut Ave. NW. Free. Call 202-633-4800 or visit nationalzoo.si.edu.