A showdown is brewing this week over the future of ISTEP, but expect a new question to be raised: could changes to state tests could put Indiana’s federal school aid at risk?

At a minimum, any change of course for ISTEP would likely require a review by the U.S. Department of Education to be sure it would not violate an agreement Indiana made in 2012 to ensure schools would be able to spend federal aid money without new restrictions.

The debate has become increasingly high-stakes as the Indiana State Board of Education and powerful state lawmakers have yet to blink on very different plans for ISTEP. Lawmakers have fewer than 10 days to sort out the dispute as legislative deadlines are looming. The legislature is expected to wrap up its work by the end of April.

The House Education Committee on Tuesday is scheduled to again discuss Senate Bill 566, which would replace ISTEP with an “off-the-shelf” exam to serve as Indiana’s state test. Meanwhile, the state board last week strongly reiterated support for its plan to overhaul the state-created ISTEP test despite growing costs.

“If a school system spends $11 billion or $12 billion in total and doesn’t know where their student are in a comprehensive way, it’s dereliction of duty,” state board member Dan Elsener said at Wednesday’s state board meeting. “This is not an unreasonable cost. This is an investment. This general thing that we are spending too much money is incorrect. Leaders of organizations need to know the outcomes.”

But Sen. Luke Kenley, R-Noblesville, and Rep. Tim Brown, R-Crawfordsville, who chair the budget-making committees in the Senate and House, testified the following day before the House Education Committee that a national test, such as one created by the Oregon-based Northwest Evaluation Association that some Indiana schools use to prepare for ISTEP, could serve as the state test and save the state millions.

Kenley said testing in Indiana has gotten off-track.

“We have a great deal of concern about where we’ve gone with this,” he said. We think we’ve put together kind of a common sense approach. We think that we need to streamline the testing. We need to make the test shorter. We need to make it more acceptable by the teachers.”

The cost of a new ISTEP, redesigned to match new academic standards approved last year, has come down as the debate has intensified. In December, state Superintendent Glenda Ritz said state tests could cost about $65 million per year once a company was hired to create the new exams, a 45 percent increase over what the state pays now.

A revised proposal from Ritz estimated the cost at $37 million per year, but on Wednesday the state board backed a proposal from board member Sarah O’Brien with an estimated to cost of about $50 million per year. O’Brien argued the actual cost could be lower.

“I understand being cost efficient, but that is not our primary goal,” board member David Frietas said at last week’s meeting. “When we get into an argument over who can do it for the least amount of money I get really concerned. Because, yes, its a balance between having a really good assessment system and the money, but for me what comes first is having a great assessment system that does what we need it to do.”

Last year Indiana dumped Common Core standards, at the urging of the legislature, to create its own standards. Common Core, shared by more than 40 other states, came with shared exams developed by two consortia of states that were projected to be cheaper than the state’s self-created tests. Kenley was among legislative leaders who pushed for Indiana-specific standards.

But the change of standards and alterations to Indiana’s test for this year quickly caught the attention of federal education officials. That was one reason it put Indiana on the equivalent of probation until it proved it could still meet the terms of the 2012 agreement, also called a “waiver.”

The waiver released Indiana from sanctions under the federal No Child Left Behind law, which could have redirected millions in federal dollars schools receive for program to help poor children to outside tutoring companies. Ultimately, Indiana won a one-year renewal of the waiver that must be renewed again this summer.

If the state changes to a different test, expect another federal review, said Mike Cohen, president of Boston-based non-profit Achieve, Inc. The group helped form the Partnership for the Assessment of College and Career Readiness (PARCC), one of the test-making consortia connected to Common Core. Indiana had been part of PARCC before Gov. Mike Pence ordered the state to withdraw.

“When I got toward the end of the bill, in effect, it says, ‘when we pick this national test, if the standards and test are not aligned, we should just change the standards to be more in line with the test,’” said Cohen, who will be in Indiana on Tuesday to testify on the bill. “What’s really critical to having the testing system approved to keep your waiver is having a test aligned to standards and valid for the purposes it will be used.”

On Thursday, Kenley said he had spoken with officials at NWEA and other test-makers, who assured him minor changes could be made to the exams they make so they would fit Indiana’s standards. Or, in some cases, Indiana might need minor revisions to its standards to make them match.

“You could add a small add-on to the test that wouldn’t take much time that would meet the summative performance that would allow us to meet No Child Left Behind,” Kenley said.

But Cohen was skeptical.

“I’m not so sure the tweaks to the test to align with the standards, or vice versa, are all that minor,” he said.

One other complication to using NWEA exams is that they are entirely online and multiple choice. Some Indiana schools have chosen to give ISTEP on paper after repeated problems with online tests, and a few schools don’t yet have the computing capacity to give online exams. Kenley said the state should consider adding money to the budget to ensure all schools have the technology they need.

But Indiana’s new standards also require students to demonstrate more writing skills than in the past, Cohen said. Achieve reviewed Indiana’s standards last year and gave them mostly high marks.

“The literacy standards have heavy emphasis on writing evidence based arguments, which is based on what the students read,” he said. “A computer adaptive test with no writing will have a hard time aligning and measuring those standards.”