WHAT Dickens said of the period of the French Revolution could be said of this period, as far as children's television goes: ``It was the best of times, it was the worst of times. . . .'' It is the best of times because several programs for children that combine wholesome entertainment and education thrive on public television and the Disney cable network. Because the Disney Channel is showing how large a market exists for good programs aimed at children and their families, it is one of the fastest-growing cable channels.
And it is the best of times because a commendable trend may be developing: A number of programs on PBS and Disney are of interest not only to children but to adults. The togetherness of family viewing is preferable to TV-watching by children in isolation. PBS's Sunday evening ``Wonderworks,'' which some critics call the best children's TV show, falls in that category; so, too, many evening programs on Disney.
In other ways it is the worst of times for children's TV. Except for NBC's fine monthly magazine, ``Main Street,'' most of commercial television is a children's wasteland. The three largest commercial networks offer no daily programs for children Monday through Friday, although there are occasional ``after-school specials.'' Saturday morning cartoon programming is a familiar routine.
The two large cable channels for children -- Disney and Nickelodeon -- are inaccessible to many families, because they lack the money for payments, or their area does not have cable.
In addition, the Reagan administration is seeking to trim the federal subsidy for the Corporation for Public Broadcasting, an important source of funding for children's programs on PBS. Indeed, the Children's Television Workshop, which brings us ``Sesame Street,'' is facing financial challenges.
But such funding is a good investment in the future. If children are going to watch hours and hours of television, as many of them do, it is far better that they watch programs that are informative and that reinforce wholesome rather than destructive urges.
Commercial networks and independent stations should note the success Disney has had with evening shows for children and families. It suggests that alternative approaches could be found for commercial TV.