3 p.m. Participate in experiments and view

science projects from 40 middle school finalists. National Academy of Sciences, 2100 C St. NW. Free. 202-334-2436.

VAREKAI -- Today at 1 and

5 p.m. Cirque du Soleil

blends drama and death-

defying acrobatics in a story about a young man's journey through a magical world. RFK Stadium grounds, 2400 East Capitol St. SE. $55-$75, students $49.50-$67.50,

ages 2-12 $38.50-$52.50. 800-678-5440.

FINDING NEMO -- Today at 1:30 and 5:30 p.m. Disney on Ice performs the undersea adventure. George Mason University, Patriot Center, 4400 University Dr., Fairfax. $15-$60. 202-397-7328.

INCREDIBLE FEETS -- Today at 3 and 4:30 p.m. Footworks Percussive Dance Ensemble blends comedy, song and dance in the Appalachian folk tradition. Smith Theatre, Howard Community College, 10901 Little Patuxent Pkwy., Columbia. $9. 410-480-9950.

I WAS A TEENAGE ZUCCHINI -- Through Oct. 31. Dr. Felix Frankenfud and his nephew Andy discover a genetic breakthrough to grow super-size vegetables, but their plans backfire when Andy turns into a giant green squash. Thomas Jefferson Community Theatre, 125 S. Old Glebe Rd., Arlington. $10, children $8. All kids wearing Halloween costumes get a prize. 703-548-1154.

THE LIGHT OF EXCALIBUR -- Through Nov. 7. Merlin the magician travels to the

future to help a teenager

named Agnes with her

problems and at the same

time obtain modern knowledge. Kennedy Center, Theater

Lab, 2700 F St. NW. $14. 202-467-4600.