What schoolchildren would ask the candidates

CHILDREN can't express their views at the polls, but six elementary-school students will face the 1984 presidential candidates in a special press conference this fall as winners of a journalism essay contest held by Scholastic News magazine.

Scholastic News, a national school publication, invited children in Grades 1 through 6 to complete the following question: ''If I could ask the presidential candidates one question, I would ask . . .'' The essay contest prompted more than 32,000 responses from children across the country.

''We became acutely aware of kids' concerns and fears about the future, especially nuclear war,'' says Helen Benham, editorial director of Scholastic News. ''(The contest) gives them an outlet, a sense that someone cares and wants to listen - all the way to the White House.''

The issues that surfaced most often in the children's questions were the threat of nuclear war and relations between the United States and the USSR, the poor and homeless, unemployment, social security, taxes, nuclear waste, and pollution.

''It's astounding how articulate they are and how deeply concerned they are, '' says Ms. Benham. She believes these politically aware children will influence their parents to pay closer attention to the issues and may play a part in getting Mom and Dad to the polls.

In March a panel of judges, including Caroline Kennedy and Art Buchwald, chose 26 finalists from each grade. Six winners, one from each grade, are now being chosen. The winners, who will participate in the fall press conference, will be announced in the May 11 issue of Scholastic News.

Here are a few excerpts from the finalists' entries:

Grade 1: ''Why are there poor people, and will they ever be happy?''

Grade 2: ''Would you allow the jobless of America to build railroads, parks, and other public buildings?''

Grade 3: ''What kinds of things could a third-grader do to make the US a better and safer place for all of us to live?''

''How would you make peace with the Russians without making us look like we are too weak to fight?''

Grade 4: ''What will you do concerning the drug abuse situation in our schools today?''

''Will you do anything to change the social security system so that when I'm old enough to collect there will be enough funds for me and my generation?''

Grade 5: ''What do you plan to do about equal rights for women?''

''What will you do to help the American farmer?''

''If the condition of the country is improving, why is my dad having such a hard time finding a job?''

Grade 6: ''Would you stop building nuclear weapons if the Russians agreed to do so too?''