This school is an outstanding school. It's doing what excellent schools do, teaching the national curriculum whilst getting their kids ready for the world they will enter when they grow up.
My college has developed a similar programme but our similar issue is many of our Black African and Caribbean students are brought up in quite strict Christian households. Yet we are specifically running sessions in religious awareness of different and no faiths as well as promoting awareness of equal opps. I have had a couple of conversations with unhappy parents about this but it remains compulsory as I want our kids to be able to function in the wider world and the job market being able to tolerate and work with the full range of different people out there. Their parent's and family faiths and embedded beliefs, if restricting and cutting the kid off from the wider world have to be challenged in compulsory education.
All part of welding together a multi faith community for the kid's benefit, not their parents. If they don't like that, I invite them to go to another college. When they see the learning as enabling their kids to better function with other people in the world of work, most parents are happy to compromise. Good on this school for standing their ground.