“When Sweden is compared with other countries, we are often at the very top and I'm proud of that. But this doesn't really apply in the when it comes to schools,” he said.
Reinfeldt stressed that Sweden needed to improve results in children's education if the country was to maintain its reputation as a top science and engineering country.
He added that he was “ready to take the step” to further lowering the age at which students are first given written grades in school.
As of this year, children in Sweden have been graded from the age of 12 (in the sixth grade), down from the eighth grade in previous years.
Reinfeldt suggested the move would allow teachers to understand faster when a struggling student needed more support.
Social Democrat leader Stefan Löfven was not impressed with Reinfeldt's plans, calling them “desperate and woeful”.
“The problems our schools have with dropping results can't have escaped anyone,” he said to the TT news agency after the speech.
Meanwhile, Metta Fjelkner, chairwoman for the National Union of Teachers (Lärarnas Riksförbund), was more positive.
“We have said that we're all for earlier grading in schools, and we're happy that Fredrik Reinfeldt has now made this connection, but first we have to wait and see what happens with the reform that's just gone through, we have to let it settle,” she told TT.