Speaker of the House Paul Ryan answers questions during a news conference at the Capitol on Dec. 1 on a bill to replace No Child Left Behind. (Win Mcnamee/Getty Images)

With Congress poised to vote on a long-overdue bill to replace No Child Left Behind, the country’s main K-12 education law, opponents on the far right and left are trying to scuttle the bipartisan measure.

Heritage Action for America, the political arm of the conservative Heritage Foundation, urged lawmakers Tuesday to vote against the measure, calling it “a step backwards for conservative education policy” because it maintains too much federal control over local schools and extends it with the creation of a new preschool initiative.

The group said it will include the vote in its legislative score card.

Meanwhile, a coalition of 100 civil rights groups, including the Southern Poverty Law Center and the New York chapter of the NAACP Legal Defense and Educational Fund, also voiced opposition, saying the legislation goes too far to weaken federal oversight of the country’s 100,000 public schools. The coalition said it was particularly concerned that the bill does not address disparities in the ways public schools discipline disabled and minority students.

At the Capitol, House Speaker Paul D. Ryan confirmed plans to bring the compromise education bill for a final vote this week. A vote in the Senate is expected to follow the House vote, most likely next week.

“We expect to have very good majority support,” Ryan said. “These are great conservative education reforms. I think it was quoted in the paper yesterday that this is the greatest devolution of power back to the states in education in 25 years. That’s impressive, and that’s why I think a majority of Republicans will be supporting it.”

A raft of national groups, from the National Governors Association to School Superintendents Association to the two major teachers unions, have lined up in support of the bill.

No Child Left Behind was due for a rewrite eight years ago and is widely seen as broken, but Congress has struggled to find agreement on the proper role of the federal government in local schools.

House Republicans passed a measure in July that would dramatically weaken the federal role; the Senate passed a bipartisan measure that shifted a chunk of power to the states but maintained some oversight responsibilities for Washington.

A bipartisan, bicameral conference committee overwhelmingly passed a compromise version that largely followed the contours of the Senate bill.

The architects of the deal — Sens. Lamar Alexander (R-Tenn.) and Patty Murray (D-Wash.) and Reps. John Kline (R-Minn.) and Bobby Scott (D-Va) — said they aimed to give states and local school districts more control while making sure that federal dollars are properly spent to help educate children, especially students who have been historically underserved.

The deal would largely dismantle the federal accountability system created in 2002 by No Child Left Behind, which required schools to demonstrate academic progress as measured by standardized test scores or face a series of escalating penalties.

It would also extinguish the system of waivers given by the Obama administration, in which states that wanted to escape the demands of No Child Left Behind agreed to embrace the preferred policies of the administration. And it would significantly reduce the legal authority of the U.S. education secretary.

Under the proposal, the federal government would still require that states test students annually in math and reading in grades 3 through 8 and once in high school, and publicly report the scores according to race, income, ethnicity, disability and whether students are English-language learners.

It would require states to intervene with “evidence-based” programs in schools where student test scores are in the lowest 5 percent, where achievement gaps are greatest, and in high schools where fewer than 67 percent of students graduate on time.

But under the proposal, states, not the federal government, would determine which actions to take in those struggling schools, deciding how to evaluate school progress, how much weight to devote to standardized test scores and whether or how to evaluate teachers. States would set their own goals and timelines for academic progress. Their plans would have to be approved by the U.S. Department of Education.

The U.S. secretary of education would be legally barred from influencing state decisions about academic standards, teacher evaluations and other education policies.

The deal leaves in place the complicated funding formulas used to determine Title 1 grants, the money sent by the federal government each year to help educate students in high-poverty schools. It does not allow Title 1 funds to “follow the student” when a low-income student transfers to a different school. The deal also does not allow federal dollars to be used as vouchers for private school tuition.

The agreement also creates a $250 million annual competitive grant program to help states plan, organize and expand preschool programs for low-income children. The grant program was a priority for Murray, the ranking member of the Senate education panel and a former preschool teacher, as well as the Obama administration.

Rep. Matt Salmon (R-Ariz.), a conservative who introduced several amendments to the bill before it passed the House, said he plans to vote against the compromise bill, citing its expansion of federal support for pre-K programs and the fact that a parental testing opt-out was watered down.

“A lot of the good stuff that we were able to get in the House bill was wiped out in the conference committee,” he said.

But Salmon said there did not yet seem to be a Republican groundswell against the compromise bill.

Mike DeBonis contributed to this report.