John Carroll Sisson, president of the Prince George's County Educators Association, was filling in 200 teachers on the progress of negotiations with the school board during a closed meeting at union headquarters in Forrestville last week.

In fact, there had been no progress. The union leadership had decided to reject the latest salary offer from the school board in the three-month old talks and asked the state superintendent of school's to delcare an impasse. The action added a new note of uncertainty to the difficult negotiations, and the leadership had to convince the teachers so they could report favorably to their respective schools. The question took two hours.

Still, throughout the meeting, while grim-faced fellow bargaining team members answered questions, Sisson periodically took the lectern, flashed a perfect smile at "his people," opening his brown eyes to the widest to punctuate his comments. Reporters looking through the glass doors could not hear the words, but the "trust me," expression was very clear.

"His personality is in his face," said one teacher, active in union volunteer work. "John is well respected by teachers and principals in the county. People see him as fair, responsible and easy to get along with."

Then Sisson went outside to tell the television cameras that hundreds of county teachers calling in sick the week before amounted to "a spontaneous outpouring of frustration," and not a union action, his baby features wrinkling with concern for what teachers might do if their frustrations were not relieved.

Sisson's boyish face and puckish grin, framed by what one school board member called "Lord Fauntleroy curls," are his trademark. They are also among the weapons he uses to bring new cohesion and a spirit of openness to the union representing the largest employe group in Prince George's Count, except for federal workers. But some school officials say that he may be getting bad advice in pursuing an original 42.4 percent wage hike demand and attempting to use confrontation-type tactics with the school board. The teachers, whose starting salary is $12,014 and rises to $22,400 after 12 years of experience and a masters degree, are the lowest paid in the metropolitian area.

"You look at Sisson, and you ask a question, 'would I buy a used car from Baby Face Nelson,'" said one school board member. "I think he's a young, gullible individual who's being used. He deserves everything he gets from this."

Sisson, 34, was born and raised in Montgomery County where he attended public schools. His father has owned a gas station in Wheaton for 33 years, giving his son a sure part-time job throughout his years in the classroom, as a student and a teacher.

At the University of Maryland in College Park, Sisson was president of the Phi Kappa Tau fraternity and played tuba in the marching band. He wore his long hair then and occasionally sported a beard, an authentic child of the 1960s.

"I believe in social change and that it can take place. The '60s to me represented a great idealsim. I've retained that idealism," he said over lunch at his favorite Forrestville restaurant, a mom and pop operation where everyone knows him as "John."

When he graduated in 1970, however, the Vietnam war was still sending idealists scurring for war-exempt jobs.

"I thought that I might get drafted, but I wasn't looking for a permanent position, so I did some volunteer work at Adelphi Elementary school," said Sisson.

At the same time he was offered the job of assistant director of housing at the huge College Park campus where he had worked during a year off from school. "I had to make a choice whether I would do it or not. It was an attractive position, but I decided that I wanted to work with kids," he said. "It really turned me on. People told me that I was really good at it."

Teaching from 1971 until 1978 at Magnolia Elementary School in Largo afforded him a chance to travel almost every summer, in the kind of "singles" style that, he says, teachers used to be able to afford inflation left their incomes behind. He has traveled extensively in Europe, West Africa and South America, taking advantage of his fluent Spanish wherever possible.

One summer he was the "Easy Rider" himself, motorcycling across the country and sleeping under the stars. It was an impulsive decision.

"I had never been on a motorcycle before. I bought the motorcycle and three days later I left," he said.

But taking over leadership of the union two years ago brought an end to carefree wandering and has left little time for biking on the open road. He cut his hair and his beard and bought his first three-piece suits so "it wouldn't look like I was wearing the same thing every day."

He has no problem with the label of a good-looking charmer leading a union of 4,300 women and 1,700 men.

"It helps in my job to project a good image and I guess good looks are part of that image," he said.

Sisson refused to comment on charges that outsiders called in to work on the contract negotiation are exerting undue influence on him, but admitted that as president he is torn between the "conservatives and the kamikazis" in this difficult contract year.

Teacher strikes are illegal in Maryland, but Sisson said that he would be willing to lead one, if "his people" want it.

"I would tell them the truth and then listen to what they want to do. If they want to strike, I will lead that strike, I will go to jail if necessary," he said.

But last week he made another quick decision to take the weekend off.

"I had two teachers come in yesterday morning who said, 'if you don't take two days off this weekend we're going to kidnap you. We've got a house and we're going to keep you,'" he said.

"I don't think that's over-protective, that's caring, nurturing each other," he said, adding, "I'm taking their advice, I'm taking my phone off the hook. . . . They're fixing dinner."