WORTH NOTING ON TV

* SATURDAY

College football on ABC

(Noon to 3:30 p.m., E.T.): The traditional Army-Navy game - where interservice rivalry reaches its most exhilarating and least detrimental form - takes place at Giants Stadium in East Rutherford, N.J. The commentary is by Brent Musburger, Dick Vermeil, and Jack Arute.

(3:30-7 p.m., E.T.): This year's Southeastern Conference championship game pits Alabama against Florida at Legion Field in Birmingham, Ala. The winner goes on to the Sugar Bowl in a game airing live on Jan. 1, 1994. Commentators for the SEC contest are Keith Jackson, Bob Griese, and Lynn Swann. * SUNDAY

Nature's Great African Moments (PBS, 8-9:05 p.m.): The majesty, the cruelty, the compelling beauty of Africa's natural history are pieced together in this mosaic of clips from the past 12 years of ``Nature.'' If there is any doubt in your mind that this series ranks at the top level of nature shows, these sequences - brief though many are - should dispel it.

The program's cinematographers have captured scenes that are hard to forget. Hawks dive at a blizzard of birds, thwarted by the very number of their prey. At lakeside, an 18-foot crocodile lunges unsuccessfully at drinking wildebeests, which leap away and then come right back to the danger zone, driven by thirst. Herds of varied animals fill the open land as far as the eye can see. A leopard - spotted face perfectly camouflaged in the shadows of the grass - searches for a motionless, scentless impala fawn he seems to know is there but can't find, and finally walks away. A cheetah chases down a Thomson's gazelle at speeds almost beyond belief, then has to wait for 20 minutes before he regains enough breath to eat his prey.

Avery Brooks is host. The show is being aired during pledge week, so expect breaks.

Booknotes (C-Span, 8-9 p.m.): The guest is former British Prime Minister Margaret Thatcher, author of ``The Downing Street Years.''

Please check local listings for these programs.