Lily Eskelsen Garcia, president of the National Education Association. (Marvin Joseph/The Washington Post)

The head of the country’s largest teachers union said that her organization does not support a bipartisan proposal in the Senate to replace the nation’s main federal education law because it does not go far enough to create equal educational opportunities for poor children.

“We keep asking ourselves, ‘Does this move the needle for kids? Will a child see something better in his or her classroom?’ ” said Lily Eskelsen Garcia, president of the 3.2 million-member National Education Association, the largest labor union in the country. “And this bill in the Senate doesn’t do it. We’re not at ‘better’ yet.”

Garcia’s comments come as the Senate Health, Education, Labor and Pensions Committee begins debate this week on a bipartisan bill crafted by Sens. Lamar Alexander (R-Tenn.), chairman of the panel, and Patty Murray (Wash.), the ranking Democrat. They have been working for months on a 600-page update of the law known as No Child Left Behind.

The bill does embrace several priorities of the teachers union, such as deleting the federal penalties attached to standardized tests, which Garcia has blamed for warping the classroom experience. It also lets states decide whether and how to evaluate teachers, as opposed to a federal requirement that says they should be graded in part on the basis of student test scores.

But Garcia said Friday that the union wants any new federal education law to address the inequities between high-poverty public schools and those in more affluent communities. Recent government data show that in 23 states, state and local governments are together spending less per pupil in the poorest school districts than they are in the most affluent ones.

When Congress enacted the original federal education law in 1965 as part of President Lyndon Johnson’s War on Poverty, it was designed to address funding inequities by sending federal dollars to states to help educate poor and disabled students and those learning English.

But those federal dollars account for about 12 percent of total education spending, and Washington’s role in equalizing resources for schools is limited in a public education system funded largely by local real estate taxes.

The NEA says Congress can address the problem by requiring schools to publish an “opportunity dashboard” that would disclose how much each school spends on teacher salaries, the number of experienced teachers and counselors they employ, access to Advanced Placement and honors courses and other indicators, so that disparity between schools is transparent.

In addition to laying bare the disparities, the union wants any new federal law to hold states responsible for reducing the resource gap between schools, Garcia said.

No Child Left Behind has judged states and school districts based on student outcomes, largely by relying on test scores. But they should also be evaluated based on inputs — whether they are evenly distributing resources from school to school, she said.

“We’ve been talking about this to every senator we can,” Garcia said. “It is time for accountability to mean that all kids are getting what they need.”

She said the union will push hard for changes in a final bill.

“This is not an endgame, this is the beginning of the fight,” she said. “Senators Patty Murray and Alexander really have tried very hard to get this to a better place, and it’s not there yet. We want to work with members of Congress, we want to move this forward . . . we want them to fix some of the things that are egregiously wrong.”

The NEA’s opposition to the bipartisan proposal sets it apart from many other education organizations that have expressed cautious optimism, with the exception of the Heritage Foundation, which also is opposed.

No Child Left Behind was due for reauthorization in 2007, but previous attempts to rewrite the law collapsed amid partisan debates on Capitol Hill about the proper role of the federal government in local schools.