A D.C. Superior Court judge levied heavy fines yesterday on the striking Washington Teachers' Union after finding the union in contempt of court for violating a week-old court order prohibiting a strike by its 5,000 members.

Judge Gladys Kessler said the fines would not be imposed if teachers return to school this morning, ending the walkout that has crippled the city's school system since last Tuesday.

Kessler said it was of "absolute necessity that the children of District of Columbia schools be provded an education." She added that federal mediators will be reporting to her each day on how negotiations are progressing between the union and the board.

Union President William Simons said afterward that the strike was still on for Tuesday morning and that he expects it to expand in coming days through the support of other labor unions with whom he has been talking.

"The membership called the strike and the membership will have to end it," Simons said. "I have no plan of calling a membership meeting tonight or tomorrow. This is union-busting at its best."

D.C. School Board President Minnie S. Woodson, who was in court to hear the judge's ruling, said she was "very glad the judge was that fair. All we wanted was to be able to get back to the negotiating table. We didn't want punitive measures. We hope things will mend."

Mayor Marion Barry said Kessler's ruling was "no compromise for either side" and continued to offer himself as an independent third party as a way to get negotiations going again. "This is not over," Barry said through press spokesman Kwame Holman. "We have to work it out together."

The judge's decision came hours after the school board held a closed meeting to review proposals being negotiated by the board and the union. The meeting was the first the board has formally held since the strike began.

The meeting was called after Barry met with eight members of the 10-member board over the weekend and proposed a compromise aimed at ending the strike and delaying the court proceeding. Barry told the board Sunday that the union would agree to his proposal and said the board's agreement was all that was necessary to get teachers back in school. However, the board members split, 4 to 4, on a straw vote to call an emergency meeting of the board Sunday night to consider Barry's proposal.

Board members said Barry's proposal was not discussed at yesterday's meeting.

"There was no point in discussing the mayor's proposal," said John Warren, school board member from Ward 6. "You don't sit down and discuss someone else's position until you are sure of your own position. We looked at every issue on the table and we are trying to decide what we will go to the wall on and what we are willing to compromise on."

The compromise proposed by the mayor would have had the union end the strike in return for a promise from the school board that no reprisals would be taken against teachers who were on strike and continued recognition of the union as the sole bargaining agent for the city's 6,000 public school teachers.

Barry also proposed that the union and board enter into fact-finding on proposals they now have on the negotiating table. Barry did not ask the board to reinstate the whole teachers' contract or the automatic union dues deductions clause of the contract, the union's financial lifeline.

The board was hesitant to meet with the mayor to consider his proposal. Board members have said they do not want the mayor to supersede their authority as elected offcials responsible for the operation of city schools. In addition, the board was suspicious of Barry's motives because Barry was endorsed by the union only months ago during the mayoral campaign.

According to board members, 21 major issues still separate the board and the union at the bargaining table. No negotiating sessions are scheduled.

Yesterday, Board President Woodson appeared before the D.C. House District Appropriations Subcommittee to brief Rep. Charles Wilson (D-Tex.), the committee chairman, on the strike.

Woodson, who was accompanied by Board Vice Preisent Carol Schwartz and school Superintendent Vincent E. Reed, told Wilson: "It seems to be a pattern of this union [to get contract issues resolved by the mayor]."

Woodson added that the board "appreciates the mayor's concern" but said the mayor's intervention "seemed to delay rather than hasten the process [of resolving the strike] and may have aborted a solution."

Meanwhile, Reed reported that 45 percent of the city's teachers reported to work yesterday, the fifth day of the strike. Reed said about 50 percent of the city's 113,000 students attended the District's 200 schools yesterday.

"We had the same number of teachers we had last Friday," Reed said, "and a few more students. Things went much more smoothly in the schools today than last week, but that's not to say that things are normal. I'm not trying to fool anybody."

A spokesman for the Washington Teachers' Union called Reed's estimates "ridiculous" and said that 80 percent of the city's teachers honored the strike and remained out of school yesterday.

After the board completed its morning meeting it scheduled a 7:30 p.m. closed meeting to continue reviewing proposals now on the bargaining table. After board members and the superintendent left the morning meeting, William Robinson, president of the Eaton Elementary School Parent-Teacher Association, gave board president Woodson a group of ballots from parents demanding that the board enter into binding arbitration with the union and agree to reinstate the union's contract to get eachers back in school.

"It's the same people that cry out for quality education who now want us to totally buckle," Schwartz said. "That's what this does," she said, pointing to the ballots that Robinson brought with him to the board's head-quarters.

Following last night's two-hour school board meeting, Woodson said that the board had reviewed the current status of negotiations but that no specific proposals had been discussed.

The judge's ruling came late yesterday afternoon after almost four full days of court hearings on the board's request that the court find the union in contempt of court for violating the judge's temporary restraining order. That orde was issued March 5, about an hour before the union went on strike.

Yesterday's ruling by the judge included a $5,000 fine on the union for every day union officials fail to comply with the judge's order against a strike.

Simons and the other nine defendants in the case were given various fines unless the strike is called off today. The heaviest was given to Simons, who was fined $500 for the first day of the strike, March 5, and $500 a day for the remainder of the strike.

Defendants who served on the union's executive board were fined $250 for the first day and $250 for each additional day. Those defendants who were union members but not on the executive board were fined $250 for the first day and $100 for each additional day.

No fines were assessed against the thousands of other teachers who took part in the strike but were not named as defendants in the court suit.

"The purpose of civil sancitions are not punishment but are remedial and coercive," Kessler said before announcing the fines late yesterday afternoon. ["If union officials] do their utmost to see to it that teachers return to work [the fines will not be imposed]."

Kessler said she will entertain "a request for further punitive measures" if it is necessary and that the additional court action could include jailing union leaders.

Part of the Barry administrtion's motivation for trying to end the strike over the weekend and stave off a contempt of court citation was fear that such a ruling could lead the union to increase the intensity of strike activities.Simons said yesterday that is precisely what he intends to do.

In a public statement yesterday, Barry said he had "no idea" whether the strike would proliferate.

Simons said yesterday that Local 36 of the International Association of Firefighters, the union representing the city's firemen, had already offered its support "to prevent union-busting." He said he would soon be talking with the leaders of other labor organizations in the area.

One key labor organization in any possible proliferation of strike activties is Council 20 of the American Federation of State, County and Municipal Employes, whose membership includes 4,000 custodians, security guards, cafeteria workers, clerical workers and teacher aides in the city schools.

Geraldine Boykins, director of the council, said yesterday, after being told of the judge's decision, that while the union had not taken any vote to launch a job action of its own, "They (the teachers) know that we will support them in whatever way we can."

"We have been gearing up. We haven't been sitting idly by," Boykins said. "We have been making preparations to do certain other things if it becomes necessary."

Throughout the first week of the strike, board members have been anxious for the court to take action against the union, hoping that the court could force the union to end the strike and return to the bargaining table.

Board members have stressed that they are ready to negotiate all proposals. On Saturday, board President Woodson asked the union to join the board in round-the-clock negotiations until a contract was agreed on. The union did not respond to the offer. The last contract between the teachers' union and the school board expired in January 1978 but the board has agreed to three extensions. The board's refusal to grant a fourth extension on Feb. 14 -- and its decision to end the union's automatic dues deductions on teachers paychecks -- led to the strike.

The temporary restraining order issued by Judge Kessler March 5 ordered the union not to strike because it would "do irreparable harm to the city." The strike is illegal under Title 5 of the U.S. Code, which prohibits public employes of the federal or District governments to strike. When she issued the restraining order Kessler also noted that District teachers signed an affidavit agreeing not to strike when they were hired by the school system.

In 1972, when the union went on strike for two weeks, Superior Court Judge Robert H. Campbell fined the union $50,000 after he found it to be in contempt of court for striking.

Simons, president of the union, said he does not expect Judge Kessler's ruling to cripple the strike.

"It [the ruling] was not unexpected," Simons said from his office after leaving court. "However I am sorely disappointed because there was nothing to compel the Board of Education to negotiate in good faith... If the board thinks this is going to stop the union, they are sadly mistaken."

Simons said the fines levied by the judge will not affect his union: "If one stops (striking) because of money, one's got no business being in this business."

In addition Simons said his union plans to step up strike action against the city schools by asking other unions to stop servicing the schools.