Fall is here. Do the wave. SEE The Sant Ocean Hall What: Take a dip into the museum’s newly opened aquatic wonderland with models of whales, prehistoric sharks, and a giant squid. Why: Find Nemo. When: Opens Sat. Daily, 10 a.m.-5:30 p.m. Where: National Museum of Natural History, 10th St. & Constitution Ave. NW (202-633-1000). The Fall Design House What: Eight local interior designers showcase rooms inspired by haute fashion in the casa couture theme. Why: Live en vogue. When: Fri.-Dec. 13. Mon.-Fri, 10 a.m.-5 p.m.; Sat., 10 a.m.-3 p.m. Where: The Washington Design Center, 300 D St. SW, b/t 3rd St. & Virginia Ave. (202-554-5053). SHOP Sugar Annual Fall Bash What: Snag 25 percent off fall merch and one-of-a-kind jewelry from local designer Debra Fabian. Why: Time to scarf some deals. When: Thurs., 4-9 p.m. Where: 1633 Wisconsin Ave., b/t Q St. & Reservoir Rd. (202-333-5331). GO Virginia Wine Festival What: Sip, shop, and savor the East Coast’s largest grape-a-thon. Why: Don’t keep it bottled up. When: Sat. & Sun., 11 a.m.-6 p.m. Where: Prince William County Fairgrounds, 10624 Dumfries Rd., Manassas (703-922-7049). Second Annapolis Warehouse Sale What: Horse, Saucy Shoes, and other great boutiques offer deep deals on summer items. Why: Summer’s in the house. When: Sun., noon–5 p.m. Where: Loews Annapolis Hotel, 126 West St., Annapolis (410-280-8845).