Like falling leaves, there is a flurry of arts and crafts shows, flea markets and fairs in the area for the last weekend of the summer. A rake-up:

ELEVATIONS is the showing, by 16 of Washington's designers and craftsmen, of original clothing, jewelry, hand-crafted accessories and hair sculpture. Cost is $5 Sunday, 4 to 6, at Union Temple Church, 2002 14th Street SE. For details call either 265-2658 or 638-6048.

AVENUE OF GLASS is the the show along Connecticut Avenue, where shops between M Street and Rhode Island display in their windows the stained- glass sculptures and panels of local professional and amateur stained-glass artists. The show and sale continue through September. Call 566-6603 or 522-6420. Quantico gets in on the action with its sixth annual ART AND CRAFT SHOW Saturday, 10 to 6 and Sunday, noon to 6 on Main Street. Free. Call 703/640-7411. Manassas' Autumn ANTIQUE AND CRAFT FESTIVAL includes quilting, weaving, and chair-caning, along with authentic Pennsylvania Dutch funnel cakes and Amish food. Free, Saturday and Sunday, 10 to 5, at 7209 Centreville Road (Route 28). Call 703/631-0590. The Prince George's County Police Department celebrates its fiftieth birthday Sunday with FIELD DAY demonstrations: canine and horse shows, helicopter rappelling, motorcycling and law-enforcement exhibits. At the Old Marlboro Racetrack grounds in Upper Marlboro, 9 to 6. Call 420-0180. Gaithersburg's COUNTRY HOE-DOWN offers a farmers' market and music as well as the arts and crafts show. Saturday 10 to 6, free. Call 948-3220. The COUNTRY FAIR AND ANTIQUE AUCTION in Ellicott City, Maryland, is free Saturday 11 to 5 with demonstrations of spinning, carding, quilting, and more. Auction begins at 1. Call 992-2483. The Animal Welfare League of Arlington gives its animals the benefit of its sixth annual BAZAAR AND YARD SALE Saturday, 9 to 4. The raffle is at 4 and a silent auction goes all day, at 2650 South Arlington Mill Road. Call 931-9241. Sully Plantation in Virginia invites you to bring those gizmos you always wondered about to ANTIQUE APPRAISAL DAY, Saturday, 1 to 5, when local appraisers will examine jewelry, silver, paintings, porcelains and other collectibles. Limit of three objects per person, cost, $3. Call 437-1794. Rosecroft Raceway begins year-round FLEA MARKETS this weekend that will continue every other Sunday. Free, 10 to 5 at 6336 Rosecroft Drive in Oxon Hill, Maryland. Call 567-5815. Takoma Park's 15th annual ANTIQUES SHOW AND SALE is Sunday, noon to 6 at 101 Philadelphia Avenue, with free displays of antiques glassware, furniture and more. Call 270-5798 or 270-4048. Washington Women Outdoors holds a free FALL FAIR Friday, 6:30 to 9 at Glen Echo Pavilion in Maryland, and invites all who want to find out about the hiking, biking, backpacking and other outdoor activities going on this fall. For more information call 301/942-8677. The 21st FESTIVAL ITALIANO offers folk dancing and lots of Italian food Sunday, 11 to 6, at the Villa Rosa Nursing Home grounds on Lottsford Vista Road in Mitchellville, Maryland. Call 423-2243. And there are some far-away fairs: Warsaw, Virginia serves up seafood and dignitaries along with the arts and crafts all day Saturday. Parachuters open the show at 9:30; Governor Dalton and Sen. Harry Byrd Jr., are opening ceremony speakers. Call 804/333-3655. And the Pearl S. Buck Birthplace Complex in HILLSBORO, West Virginia, holds its first Fall Festival Saturday, 10 until dark; crafts made include lye soap, apple butter, cider, quilts and more. Call 304/645-1812.