New Zealand’s education minister has launched a probe into an “impossible” math test with questions so hard, they left some students in tears.

After taking the National Certificate of Educational Achievement level 1 math exams Monday, pupils complained the questions were just too tough and contained concepts they’d never been taught, the New Zealand Herald reported.

“It was impossible to work out what the questions wanted, even after you spent precious time working them out, what they wanted was often entirely new concepts,” star student Maria Dussler told the paper.

Another student who said he had a 100 percent grade point average told the paper the test was “incomprehensible in parts.”

“In some cases, calculations were impossible given the lack of information,” he wrote.

One distraught and angry parent said kids she knew were “just in pieces,” over the exam, Stuff.co reported.

A question contested by students involved quadratic equations– which are not taught until level 2 in New Zealand– and two other questions were described as “effectively identical,” meaning students would be penalized twice for not knowing the answer.

So far, 22 math teachers signed a letter of complaint to the Ministry of Education and the New Zealand Qualifications Authority which administers the test.

“For a national exam you would expect better,” the letter’s author, teacher Jake Wills said. “We want good exams.”

But the qualification authority said they were still confident in the quality of the tests despite complaints.

“All NCEA assessments are aligned to the standard and the NZ Curriculum,” said NZQA Deputy Chief Executive Kristine Kilkelly. “Students may find some questions in examinations more difficult than others, especially those parts of the question aimed at excellence. Parts of the examination will be challenging, but students often do better than they expect.”

Last year’s level 1 exams were also criticized for being too tough and a level 3 exam question had an error which made it impossible to answer, Radio New Zealand reported.