Thiesfeldt did not respond to multiple interview requests. Milwaukee Public Schools officials also declined to be interviewed until the bill has been amended. But in her testimony Milwaukee Superintendent Darienne Driver laid out several challenges facing her district, such as an 82 percent poverty rate and chronic absenteeism.

Yet during the hearing, when asked by Milwaukee Democrat Christine Sinicki , who asked if the measure would open the door to for-profit education, Thiesfeldt said, “I suppose it does.”

“There isn't any intention on my part to try to have a whole bunch new, independent charter schools in the state,” Thiesfeldt told Wisconsin public television . “My preference would be is that it would not reach that point.”

Under the proposal, failing schools would have seven years to improve their scores and avoid conversion to a charter school.

Other opponents of Thiesfeldt’s bill cried foul at the start of the hearing when he declared that one of its key components, the ARB, would be removed. They argued that this fundamentally altered the legislation and the hearing should have been postponed until a revised version of the bill was ready. Still others raised concerns about the stipulation that failing schools must convert to an independent charter status , thus circumventing locally elected school boards’ control.

Nonpartisan groups such as the Wisconsin Association of School Boards see the bill crunching public school budgets and funneling those resources into independent charter schools.

AB 1 , drafted by Rep. Jeremy Thiesfeldt, R-Fond du Lac, aims to change Wisconsin’s current school accountability system, which was approved in 2014. As written, it would establish an Academic Review Board (ARB) that would have the power to incentivize and punish publicly funded schools based on performance. The board would have the power to approve alternative assessments in lieu of the state exam to determine how schools are performing. The bill also sets out the methodology for measuring school performance and stipulates that the ARB has the authority to convert a failing public school to a charter school.

“This legislation can't punish and starve our students of the resources they need to learn,” Mizialko testified, “and then declare that our students are failures.”

Recovering her composure to register her opposition to the school accountability bill being heard, she argued that it would take resources away from children who have already been “forced through the cracks.” Like many other critics of the bill, Mizialko said the bill ignores schools’ broader socioeconomic context and the effects of poverty on children's learning.

MADISON, Wis. — At the end of a long day of public testimony, a young teacher broke down in tears in the center of the hearing room. “We have students who don't own a pair of socks,” Amy Mizialko, a special education instructor in the Milwaukee public school system , told the Wisconsin State Assembly's Education Committee. “And they walk to school every day in the winter.”

Our members have been quite clear that private and religious schools…should be subject to the same accountability, which means taking the same test as public schools take.”

Also during the hearing, Sinicki noted that the bill would shift nearly $900 million dollars — nearly a fifth of the $5 billion school aid budget — away from the public school system. That drain raises concerns for supporters of public schools.

“Especially in the rural areas, there are a lot of [school districts] that are one or two buildings,” said Sen. Paul Farrow, R-Pewaukee, who introduced a competing school accountability bill in the Senate without the mandate that failing schools convert to charter status. Some rural areas have just one elementary or middle school for an entire district, making school choice impossible. Furthermore, these areas often lack financial resources.

“That's one of the reasons why we didn't look at [automatic conversion] as we were moving forward,” he explained. Such a mandate would mean eliminating the only public option in these rural areas. Farrow's bill also differs from the Assembly version in the makeup and function of the review board.

Parents like Joanne Juhnke, whose youngest daughter is autistic and suffers from epilepsy, are worried that AB 1 would siphon resources from public schools, which provide for educational supports for special-needs children.

“If you look at independent charters and cognitive disabilities, the public schools educate a number that is five times greater,” Juhnke said. “These are students where the challenges are great. And we're looking at schools that don't educate a fair proportion of the students with challenges.”

Conservatives and progressives alike have voiced opposition to Thiesfeldt’s proposal. Dan Rossmiller, director of government relations for the Wisconsin Association of School Boards said he suspected interest groups pushed Thiesfeldt to drop the controversial ARB provision.

“I think the bulk of the pressure was coming from the private schools and those in the voucher program,” Rossmiller said. “They did not want to be subject to a board chaired by the state superintendent.” The superintendent is an elected office in Wisconsin and is not appointed by the governor and therefore has more autonomy to administer the law.

Maureen “Mo” May-Grimm, who lives in the rural community Mineral Point, said she attended the hearing out of concern that big money, outside interests are promoting school privatization.

“The big organization that concerns me is the American Federation for Children,” she said, stating that the group made large campaign contributions when she ran for the state assembly in 2012. The Wisconsin Democracy Campaign reported in 2013 that the group spent approximately $400,000 on campaigns since 2010. Its website states that it is “creating an education revolution” to provide parents with more choices.

While May-Grimm and others speculate the group is a player in AB 1, Jonas Persson of the Center for Media and Democracy said the bill closely resembles two education bills supported by the American Legislative Exchange Council, a conservative legislation mill backed by billionaire brothers Charles Koch and David Koch. Those bills are the A+ Literacy Act and the Indiana Education Reform Package.

The Assembly bill would allow performance metrics for voucher and charter schools that receive public funds different from those for public schools. While public schools must take the state test approved by the Department of Public Instruction, the Assembly bill would allow other schools to use alternative exams approved by the ARB. The Wisconsin Association of School Boards says that would result in a step back from current policy, which requires voucher students to take the same exam as public school students.

“Our members have been quite clear that private and religious schools … should be subject to the same accountability,” said Rossmiller, “which means taking the same test as public schools take.”

The talk of accountability didn't sit well with Rachel Schlueter, a mother of two school-age children and a teacher for 25 years in Milwaukee’s public schools. She said the call for accountability is missing the target.

“We've seen so many voucher schools up and leave in the middle of the night,” she said. “Just recently, before vacation, we had a high school that actually left around 200 students without a school, that their parents had to look for an alternative right after vacation.”