A coalition of city officials and community leaders announced yesterday their opposition to a November ballot initiative that, if passed, would permit city residents to claim educational tax credits on their city income taxes.

The initiative, under which District residents could write off up to $1,200 in expenses for each child they have enrolled in public or private schools, is being pushed by the D.C. Committee for Improved Education. That group is a local offshoot of the National Taxpayers Union (NTU), which lost a similar petition drive in California in 1979.

Some of those in the opposing coalition charged yesterday that the initiative's backers were hoping for a victory here so that they could argue elsewhere that its approval by the predominantly black city proves there are no racial overtones to the proposal. They charged that it would primarily benefit more affluent families with children in private schools.

"It's a racist initiative [and] this is a predominantly black city," said council member John A. Wilson (D-Ward 2), one of the coalition members. "If it passes here, it will let them say that there is nothing racist about it."

The formation of the opposition group, led by Council Chairman Arrington Dixon, now puts most of the city's elected officials as well as a broad cross section of Washington's community organizations squarely at odds with the citizens' initiative, which two days ago won preliminary approval for a spot on the November ballot after its supporters collected over 27,000 signatures.

"We have a unanimous group here. We are all united in opposing the absolutely absurd, devastating proposal," said council member Polly Shackleton (D-Ward 3).

Joining the coalition were the American Civil Liberties Union, the D.C. League of Women Voters, Parents United for Full Public School Funding, the American Federation of Government Employees Council 211, the local NAACP, and other groups.

The allied opponents of the referendum all said that, if passed, the initiative would drain the city government's treasury of up to $40 million in lost taxes each year and would destroy public education here.

Under the proposal, taxpayers would be able to claim as a tax credit up to $1,200 in expenses for each family member attending kindergarten through 12th grade, whether the student attends public or private schools. Deductible expenses would include private school tuition, bus and book costs, and any other expense directly related to school attendance.

The credit would be less for families earning below $20,000 a year. Nonparents who help put children through schools also would qualify for credit, and corporations would be allowed to write off up to 50 percent of their District corporate taxes by paying for local children to attend public or private schools anywhere in the world.

Backers of the initiative argue that the tax credits would benefit low- and middle-income city residents by encouraging donations to public schools, where most lower- and middle-income families send their children.

The $1,200 educational tax credit -- backers shun the title "tuition tax credit" since all educational expenses can be claimed -- was first proposed by Libertarian Ed Clark in his 1978 campaign for governor of California. After Clark's defeat, the National Taxpayers Union revived the proposal in 1979 as a California ballot, initiative, but failed to collect enough signatures to win a spot on the ballot.

Clark revived his educational tax credit plan in one of four white papers for his presidential campaign in 1980. The initiative here, which is similar in most respects to the Clark proposal, was written for the Washington D.C. ballot by Jule Herbert, a District lawyer who was Clark's 1980 campaign treasurer.

Libertarian Party workers helped collect the 27,000-plus signatures to qualify the D.C. initiative for a spot on the November ballot. The full-time coordinator for the local ddrive is Jo Ann Willis, a Clark campaign worker.

Bruce Powell, an administrative asistant for the Libertarian National Committee here, said that the local Libertarian Party also will field a slate of candidates for the school board elections in November and will make the educational tax credit drive a campaign platform plank.