``Children's theater'' can refer to children performing charmingly for other children, or at worst, grown-ups dressed as dancing vegetables, trying to entertain an audience of fidgety kids. But the concept reaches what may be its highest level in Theatreworks USA - a superlative family-oriented theater company that has an Off Broadway home here in New York and also tours the United States, playing in schools and theaters.
Theatreworks productions are professional, highly entertaining, and never condescending. Behind all the fun, they project a sense of strong values. The plays seem to appeal to every age, from three on up to adults.
Even the smallest children sat spellbound at a play I attended, titled ``Lady Liberty,'' about the far-from-childish subject of immigrant life in America. The usual restless chatter and loud outbursts were practically absent from these performances; and there was enough meat to keep the older children and even the adults interested. In fact, quite a few adults came without children.
``Lady Liberty'' is the tale of a young Slovak girl, Maria, who comes to America innocently believing she will find a brand new life right off the bat. It's an inspiring, colorful exploration of brave hope that survives phases of discouragement, struggle, and even outrage, as Maria and her friends come up against one barrier after another.
Finally, their renewed determination results in an idea to start a business of their own - the message being that a right idea put into practice can overcome even the most stubborn obstacles. This message was charmingly conveyed in a song entitled ``It's the Thought That Counts.''
By sending out several troupes at a time, Theatreworks USA manages to give more than 1,000 performances a year, reaching about 800,000 people, mostly in schools around the US.
The plays feature fresh-faced, dynamic, talented actors - all adults - and are written by first-rate writers. There are usually five or six actors and actresses in each production, and the company employs about 100 actors and stagehands in the course of a year.
The staging is simple but imaginative, and the music and lyrics are inventive and witty.
In an interview at Theaterworks' Upper West Side offices, Jay Harnick, the group's artistic director, explained, ``We commission all the works that we do. We get the best authors, composers, lyricists available to us.''
Among these are Ossie Davis, Thomas Babe, Saul Levitt, Mary Rodgers, Joe Raposo, Albert Hague, John Morris, Alice Childress, and Gary William Friedman.
Charles Hull, managing director, added, ``We've had some terrific actors through the years. Henry Winkler was in our Bible stories. Sherman Hemsley was in a play about Martin Luther King. Last year we had our first Academy Award winner, F. Murray Abraham.''
Mr. Harnick became interested in theater for young audiences in 1961 when he directed a play titled ``Young Abe Lincoln.''
It was the first musical for young people to play on Broadway. Soon Harnick joined producer Robert K. Adams to form Harnick-Adams Productions. The two men worked together for a number of years, developing more material and touring.
Then, in 1967 the Performing Arts Repertory Theatre, the precursor of Theatreworks USA, was born.
Mr. Hull explained, ``Over the years we developed over 30 shows, many of them histories or biographies, some of them story-theater - Hans Christian Andersen, Grimm's stories, and Bible stories.''
Many of the plays are biographical, in keeping with the ``Young Abe'' precedent. These are popular, especially in schools.
``We come out of a long history of touring the schools,'' said Hull. ``The administrators see it as a way of having something good, something theatrical in their school, and yet being able to justify it, because it does tie into the curriculum.''
Says a school official from Highland Springs, Va., ``After eight years of booking productions into the school system, K through 12, I feel that I have finally found a company that holds to our standards of artistic quality. The quality is evident in the performance, style, visual impact, and also in the ability of the company to educate through entertainment.''
``When the Cookie Crumbles, You Can Still Pick Up the Pieces'' is a right-to-the-point musical revue about divorce. ``There have been a lot of kids plays written about divorce,'' Hull said, ``but it's a tough proposition to tackle that subject and make it say something honestly and yet be entertaining. So Jay suggested that we use the revue format - songs, skits, and so on.''
``We were trying to create a show that would offer support to kids,'' said Harnick, ``one that says that if we talk about it, it's better than not talking about it. And although divorce is a traumatic experience, life goes on, and there's a way of picking yourself up and dealing with it.''
One little girl from the Bronx who saw ``Cookie'' wrote a letter to Theatreworks, stating, ``When I saw the show I thought and felt what was going on. I told my friend sitting next to me, that's what I'm going through.''
``We don't produce the plays with the idea of promoting any particular ideology or point of view,'' added Hull, ``or even to tell kids to work harder or be nice to your mother or listen to your teacher.
``We really approach it as theater people. We have to come up with terrific entertainment - that's what theater is all about, and hopefully it says something along the way.''
For some time both he and Harnick had been hoping for a permanent residence for the company in New York. Happily that dream came true last year, when the group took up permanent residence at the Promenade Theater here. Plays for Theatreworks' 1986-87 New York season (though Feb. 22) include ``Lady Liberty,'' ``Merlin,'' ``The Emperor's New Clothes,'' ``Martin Luther King Jr.,'' ``Sherlock Holmes and the Red-Headed League.''
Theatreworks USA will be making its nationwide tours the rest of the year.