A school led by former government social mobility tsar Katharine Birbalsingh is being challenged in the High Court over a policy allegedly amounting to a "prayer ban".
Michaela School in Brent, north London, introduced a policy in March 2023 "banning prayer rituals".
A Muslim student at the school told the High Court on Tuesday the policy is discriminatory.
The school will set out its defence in court on Wednesday.
The hearing was told that the school's stance was first introduced in March last year by its founder and headteacher Katharine Birbalsingh and later "re-made" by its governing body in May.
In the legal action against the free school's governing body, the Michaela Community Schools Trust, the student claimed the decision breached her right to freedom of religion.
The pupil, who cannot be named for legal reasons, told the court the rule had "fundamentally changed" how she feels "about being a Muslim in this country".
She described the ban as "like somebody saying they don't feel like I properly belong here", the hearing was told.
Representing the student, Sarah Hannett KC told the court about half of the schools roughly 700 pupils were Muslim and the policy had the "practical effect of only preventing Muslims from praying, because their prayer by nature has a ritualised nature rather than being internal".
