This weekend, the route to a car lover's heart probably winds through the Budweiser World of Wheels at the D.C. Convention Center 6 to 11 Friday, noon to 11 Saturday and Sunday. More than 300 custom cars, rods, vans, trucks, race cars and bikes will be on display for you and the show judges to check out. Stars include the Ferrari Testarossa, the Lamborghini Countach and rock group ZZ Top's '48 Pontiac limo. Admission to the show is $7; $2.50 for kids 6 to 12. Call 371-5025.
THE PICK OF THE SLIMS
Women's tennis has come a long way to the Virginia Slims of Washington tournament's $300,000 purse. Competing this weekend at George Mason University's Patriot Center are Martina Navratilova, Hana Mandlikova, Gabriela Sabatini, Pam Shriver and many others. Semifinals are at 10 and 7 Friday ($9 and $14) and 1 and 7 Saturday ($16). Finals are at 1 Sunday ($18). Tickets are available for everything by phone at 432-0200. Call 429-0690.
YOUNG AT HEART
Baby boomers and boomettes might want to check out folk duet Rosenshontz at 3 Saturday. Vermonters Gary Rosen and Bill Shontz use guitars, flutes, clarinet, saxophone and humor in their hip children's show at Northwood High School (at Arcola and University in Wheaton). Tickets are $4; $3 for groups of 10 or more and are available at the House of Musical Traditions (7040 Carroll Ave., Takoma Park), Olsson's, and Wheaton Plaza's Cuddle Corner. Call 337-4313.
Meanwhile, kiddie-rock and folk are in store at the National Theatre's Saturday Morning program with Takoma Park singer-songwriter Marcy Marxer. Shows at 9:30 and 11 at 1321 Pennsylvania Ave. NW; seating is on a first-come, first-served basis. Call 783-3372.
The 47th annual Westinghouse Science Talent Search exhibition showcases the projects and inventions of the
40 national high school winners
1 to 4 Saturday and Sunday at the National Academy of the Sciences. Projects -- involving space-based laser ballistic missile defense, termite control using vibrations and the thermal properties of composite materials -- can be seen for free at 21st and C streets NW. Call 463-9861 for information.
"Wintersong" is a folk arts mini-festival 1 to midnight Saturday at the Adult Recreation Center at Bentz and West Second streets in Frederick. Following daytime music and dance workshops (including instrument-making, swing dance and storytelling), hear folk musician John McCutcheon at 7. Following that, show off what you've learned at a 9 p.m. dance with music by the Critton Hollow String Band. Tickets are $6 (for everything) or $2 for the workshops. (A workshop for hammered dulcimer with McCutcheon at 4:30 is $15.) Call 301/694-1436 or 301/663-8687.
Folk singer and wit Tom Paxton performs at the Maryland Hall for the Creative Arts at 8 Saturday; Washington's own folk-singing Smith Sisters open the show. Tickets are $10 at the door, Greenfield Street off Spa Road in Annapolis. Call 261-1553. (The Smith Sisters also perform at 9 Friday at Dylan's Cafe, 3251 Prospect St. NW in Georgetown. Cover is $5. Call 337-0593.
Martin Luther King Jr. Library plans "A Musical Celebration in in Honor of Black History Month" at 2 Sunday with ragtime, jazz and gospel music by pianist Hubert Dixon, violinist Shanon McCain, violist Ed Lewis and the Canaan Baptist Senior Choir, among others. The library is at 901 G St. NW. Free. Call 727-1285.
Also specially for Black History Month, the Congolese mass "Missa Luba" will be performed by the St. Luke's Episcopal Church Choir and the National Association of Negro Musicians at 5 Sunday. It's free at St. Luke's, 1514 15th St. NW. Call 667-4394 for more information.
Members of the Virginia Chamber Orchestra begin a new series this weekend at the Lyceum. The Virginia Chamber Players perform at 5 Sunday; its members are drawn from the Orchestra at large and this week's cast includes violinist Margaret Thomas, flutist Meta Orear and cellist Sue Kelly, all at 201 South Washington St., Alexandria. Free. 931-6867.
Earlier Sunday at the Lyceum, see how 18th- and 19th-century folk dressed for success in a "Fashion Promenade" fashion show, whose model/actors will show slides and tell stories about their historically accurate lifestyles. Free, 3 p.m. 838-4994.
REST OF THE BEST
Beat Generation poet Allen Ginsberg reads from his work in the Baird Auditorium of the Smith- sonian's Museum of Natural History at 8 Friday; $10 through the Resident Associates Program. Call 357-3030 . . . Uruguayan guitarist Eduardo Fernandez performs a memorial concert in honor of Andre's Segovia at 8 Saturday in the Memorial Chapel (off U.S. 1), the University of Maryland, College Park. It's $9; $5 for students and seniors. Call 454-4241 . . . The Hunt Valley Antiques Show features the furniture, miniatures and collectibles of 60 dealers noon to 9 Friday and Saturday and noon to 5 Sunday. It's $5 at the Marriott Hunt Valley Inn, I-83 at Shawan Road 30 miles north of Baltimore. Call 301/235-2502 . . . Expo '88, the Home and Better Living Show is at the D.C. Armory 3 to 10 Friday, 11 to 10 Saturday and 11 to 8 Sunday. Admission is $5; free for under 13 with a parent. Call 547-9077 . . . More than 70 artisans are expected at the Arts and Crafts Expo at Arlington's Ballston Common Mall 10 to 9:30 Friday and Saturday and noon to 5 Sunday. It's free. Call 751-3050.