On The Weekend Watch:
A SERIOUS SUBJECT -- It is a different world for today's young people when they contemplate their emerging sexuality. The mortal danger of AIDS is the topic of "A Different World" on NBC tonight (8:30, Channel 2). Whoopi Goldberg guest stars as a teacher who discovers that one of her students (Tisha Campbell) has contracted the virus. The show's creator, Bill Cosby, appears early on to introduce the sobering subject.
A REAL ODD COUPLE -- One of television's more interesting duos for many years, in commercials and on series, are comedians Anne Meara and Jerry Stiller. And on Friday's edition of "American Playhouse" on PBS (at 9 p.m., channels 22 and 67), the real-life spouses star as a retired couple in a Florida complex who become amateur sleuths. "The Detective" is the second part of the "Playhouse" trilogy based on the Sunset Village stories of Warren Adler.
A PREGNANT PAUSE -- Mothers-to-be might be interested in a special scheduled Saturday on WJZ-Channel 13. "If You Are Pregnant," at 8 p.m., is an hour-long study of the importance of prenatal care in producing healthy babies.
A LATE NIGHT RETURN -- A new edition of NBC's "Saturday Night Live" (11:30 p.m., Channel 2) is scheduled to feature guest host Catherine O'Hara. The talented comic actress, you may recall, was one of the headliners on the old "SCTV Network" late-night Friday series in the early 1980s.
A SUNDAY PREMIERE -- The Fox network introduces a new series at 9:30 p.m. Sunday (Channel 45), the first spinoff from the fourth network's successful "Married, With Children." It is "Top of the Heap," following the parent show and featuring Joe Bologna as Al Bundy's friend, Charlie Verducci.
A SPORTS CAVALCADE -- From the Orioles to auto racing, fans have some options. The Birds are in action against Texas three times on Channel 2: at 8 p.m. Friday, 8:30 p.m. Saturday and 3 p.m. Sunday. Perhaps the most prestigious golf tourney of the year, The Masters, is live from Augusta on CBS (Channel 11) at 3:30 p.m. Saturday and 4 p.m. Sunday. On "ABC's Wide World of Sports" Saturday (4:30 p.m., Channel 13), former Olympic champion Mark Spitz is profiled in connection with his comeback attempt to once again compete in the Olympiad at the age of 42. And two good auto races are scheduled for coverage: the Grand Prix of Miami at 1:30 p.m. Saturday on NBC (taped coverage, Channel 2) and the Grand Prix of Long Beach, televised live at 4 p.m. Sunday on ABC (Channel 13).
A CABLE GOODBYE -- "The Days and Nights of Molly Dodd" finally comes to the end of its remarkable post-network run on the Lifetime basic service, with a sweet swan song from star Blair Brown and the rest, at 10:30 p.m. Saturday.