The government last week defeated an opposition motion calling for an end to standardised tests. However, it remains embroiled in a bitter row over publishing league tables in January, which led to a mass boycott of national tests by teenagers.
"Valuable resources are being used to rank schools and costs this year have exceeded initial predictions," said Rolf Reikvam, education spokesman for the opposition Socialist Left Party.
The past two years have witnessed a significant shift away from Norway's traditionally social democratic education system, with centre and right-wing parties increasing their control.
But tension boiled over in January when the government published, for the first time, school league tables based on scores in national tests. These were introduced last year to assess pupils aged nine to 17 in core subjects, including Norwegian, maths and English.
Although the directorate for primary and secondary education said the results are "primarily for policy-makers in education", pupils and teachers fear the league tables are an attempt to introduce market forces into education.
In protest, 25,000 15 and 16-year-olds boycotted the first round of the tests in January.
"League tables will force schools to compete against each other," said Solveig Tesdal, the 21-year-old head of the School Student Union of Norway, who called for the boycott. "Too much class time is being spent drilling students on how to pass the test."
She also said the tables are misleading. "Schools with a high percentage of immigrant pupils, or from poorer areas, appear much worse."
When around a quarter of all 15 and 16-year-olds handed in blank exam sheets on January 25 and 27, the government took notice. In some counties, the figure was much higher, with 59.7 per cent boycotting in Nordland.
At the end of the first day of tests, education minister Kristin Clement demanded that schools fulfil their legal responsibility to ensure pupils completed the obligatory tests. She also warned pupils their actions could seriously affect their school-leaving grades.
But Ms Tesdal said: "Teachers can take a pupil's performance in the national tests into some consideration, but final grades are meant to fully reflect work done throughout the year. And grades are set by the teacher, not the government."
However, Ms Clement's comments did persuade many more pupils to turn up for the second day of the tests. In Oslo, for example, only 16 out of 1,148 pupils spoken to by Aftenposten newspaper boycotted that day's written English exam.
"I think most are scared of boycotting in case it affects your grade," Katarina von Sydow, 15, a Year 10 pupil at Rusel?kka skole, told Aftenposten, "especially those of us where it counts as part of our final school grade."
But Helga Hjetland, head of Norway's largest trade union for teachers, said that results for schools where more than 20 per cent of pupils had boycotted tests made league tables worthless.