A coalition of unions and parent activists launched a petition drive yesterday to amend the city charter to ensure that class sizes in New York City would be comparable to those in the rest of the state.

If the proposal of the coalition – called New Yorkers for Smaller Class Sizes – made it onto the November ballot and received enough support in the election, at least 25% of the $5.6 billion ordered by the court in the Campaign for Fiscal Equity case would be spent on reducing city class sizes, proponents of the measure said.

New York City currently has the largest class sizes in the state, exceeding statewide averages by 10% to 60%, depending on the grade level, according to data provided by the United Federation of Teachers.

“Small class sizes, qualified teachers, safe schools, and a laser-like focus on the lowest-performing schools are the key ingredients to improving student performance,” the teachers union president, Randi Weingarten, said. “We must ensure that the court ordered resources are not squandered, but go toward reducing class sizes.”

The president of the Hispanic Federation and chairwoman of New Yorkers for Smaller Class Sizes, Lillian Rodriguez-Lopez, said reducing class sizes would help narrow the achievement gap and curb drop-out rates.

“The only way to address the continuing crisis of oversized classes in New York City public schools is to make smaller classes a matter of law, rather than an annual budget negotiation,” she said.

The coalition attempted to put the question of class sizes on the ballot two years ago after collecting 114,000 petition signatures. That time, Mayor Bloomberg bumped the item from the ballot. This time, according to a lawyer for the coalition, Jerry Goldfeder, if the mayor decides not to let New Yorkers vote on the item, it will automatically be on the 2006 ballot.

The coalition’s new initiative comes months after Justice Leland DeGrasse of state Supreme Court in Manhattan said the city schools deserved $23 billion in extra aid over five years. Although various groups have listed priorities for spending the money, there is little agreement on how the bulk of the funds should be spent. It is also unclear when the money will make its way to the city’s public schools, because Governor Pataki continues to stall any change to the state’s education aid formula as he appeals the court order.

A spokesman for the city Department of Education, which has questioned the worth of pouring more money into creating lower student-to-teacher ratios, defended the Bloomberg administration’s record on class size and criticized the coalition’s new initiative in a statement.

“A ballot resolution is not the way to reduce class size,” the communications director for Schools Chancellor Joel Klein, Stephen Morello, said. “This administration has reduced or contained average class size at every grade level, and we are not waiting for CFE or a ballot to make it happen.”

He added that reducing class sizes is a key part of the city’s five-year capital plan and its strategy for spending the CFE operating funds. Together, he said, the department plans would reduce kindergarten through third-grade classes to no more than 20 students. The statement did not address class sizes in the upper grades.