WORTH NOTING ON TV

* SATURDAY

Martin Luther King Jr. National Holiday Parade (TBS, 12:05 -1:35 p.m., EST): The Atlanta Buffalo Soldiers Cavalry Unit - representing black troops who helped settle the West - is one of the features in the live coverage of this national event. Also taking part is the Michigan Black Horseman's Association and the Double 00 Riders, two groups devoted to introducing inner-city and disadvantaged kids to the fascinating heritage of black horsemanship. The event is hosted by actor Charles Dutton, singer Nancy Wilson, and sports reporter Craig Sager.

Challenge (The Discovery Channel, 9-10 p.m.): Anyone for swimming with Great White sharks? It's one of the ``sporting activities'' examined in this edition of the hair-raising weekly series, which is a kind of lexicon of derring-do. The show's host, Tim McCarver, is an ABC-TV sports personality and former major league baseball catcher who looks at several dangerous pursuits, including glacier-climbing and speed skating. * SUNDAY

Booknotes (C-Span, 8-9 p.m.): The guest is Carolyn Barta, author of ``Perot and His People: Disrupting the Balance of Political Power.''

The Russia House (NBC, 9-11:30 p.m.): Network premiere of the 1990 feature film about a British publisher (Sean Connery) asked to smuggle a scientific manuscript containing Soviet state secrets to the West. His intermediary is a beautiful Soviet woman (Michelle Pfeiffer) with whom Connery falls in love. The film script was adapted by British playwright Tom Stoppard from the John Le Carre novel, and if it sounds like a spy thriller conceived before the breakup of the Soviet Union and now showing its age, you're right. But the setting in Moscow and Leningrad is evocative.

Please check local listings for these programs.