SATURDAY NBC: The Children Nobody Wanted (9-11 p.m.) - another made-for-TV dramatization of a real-life situation - this one a bachelor father who adopts unloved kids and fights neighborhood prejudice.
PBS: Nova (8-9 p.m.) - This top science series on TV examines the phenomenon of twins, through fascinating case histories.
ABC: A Long Way Home (9-11 p.m.) - Timothy Hutton searches for his long-lost abandoned siblings in still another made-for-TV dramatization of real events.
NBC: Father Murphy (8-9 p.m.) - Michael Landon's new family-oriented sitcom. It may survive ''Little House'' demise.
PBS: Odyssey (9-10 p.m.) - A fascinating examination of an operating forge and woodworking shop dating from the 19th century.