JEFFERSON CITY, Mo. (AP) — Missouri education officials on Wednesday said results from two statewide tests can't be used to gauge how well public school districts are educating high school students.

Education Commissioner Margie Vandeven told reporters that the high school Algebra I and English II end-of-course assessments from this past school year are being tossed out because they lacked "year-to-year comparisons." They won't be used as part of accountability metrics to determine how well schools are doing and whether they've progressed over time.

"That's absolutely our primary concern, is making sure no one is negatively penalized for this type of experience," Vandeven said.

The department noticed potential issues when the results were delivered in late July, Vandeven said. An advisory committee on Aug. 18 recommended that both the Algebra and English test results not be used in school metrics.

Vandeven declined to provide more details on what went wrong with the tests, but she said they're holding Minneapolis-based developer Questar accountable. Department of Elementary and Secondary Education attorney Bill Thornton said the agency is hesitant to discuss more specifics because the issue might end up in court.

A request for comment to Questar was not immediately returned Wednesday.

The state first started working with the company in 2011. Vandeven said the agency followed required procedures in contracting with Questar.

Vandeven said this past school year's tests still work in terms of gauging student proficiency and could be used both in students' grades and in determining eligibility for what's called the state's A+ Scholarship to community colleges.

This past school year was the last during which those tests will be used because the state is switching to new tests this fall to match revamped learning standards.

"We applaud our teachers and students for their commitment and hard work throughout the school year, and we must assure them that their work is appropriately represented," Vandeven said.