Germany’s national teaching union DL has condemned a court ruling which forced a primary teacher to award higher grades to a pupil, and warns that it could lead to a flood of similar cases.

The 10-year-old girl from Lenggries, Bavaria, missed out on a place at grammar school as her test results were not high enough.

After discussing the exam result with their daughter, the girl’s parents, who cannot be named for legal reasons, decided that the teacher’s marking system was flawed and took the case to court.

The couple’s lawyers argued that the test questions were ambiguously phrased and could therefore not be answered correctly. They also demanded that the child be marked up and allowed to enter grammar school.

Five judges at the Bavarian administrative court agreed and ordered that the marks on one assignment be increased by two grades, giving the girl top marks. Another paper was awarded one mark higher.

Joseph Krauss, chairman of the teaching union, said he was “far from happy” about the ruling and said there were real concerns that other parents would follow suit.

“Teachers may feel they have to be more generous with their marks or make the tests easier, allowing pupils who are not of a high academic standard to attend grammar schools,” he said.

The decision has also been condemned by the Bavarian parliament. “We can only hope that local governments will ban court decisions on school matters,” said Mr Krauss. “We have governing bodies to ensure that schools are run fairly.”

Birgit Walther, a spokeswoman for the court, defended the ruling. “This case was not only about unfair marking but the future of the child,” she said. “The judges acted in the best interest of the child by allowing her to reach her full potential by going to a school of higher academic standing.”