In many parts of Canada (and, of course, other parts of the world), there are two systems of schooling in place: a secular system that does not explicitly endorse any particular religious faith (though can implicitly do so), and an explicitly religious system. In Canada, both of these are funded by the government, and it’s deeply problematic.
According to the Globe and Mail, proponents of the system believe that “(…) Catholic schools provide better education, structure and discipline than public ones (…)”, a claim which is certainly up for debate. In any case, religious schools typically have a list of requirements for both students and employees that go beyond the workplace, and impact their daily lives beyond school property. Many require that teachers be of a particular religion (in the case of Canada, it’s usually Catholic), or that they abstain from certain behaviours (mostly, unsurprisingly, focused on homosexuality). Others limit people who may speak at their schools, again largely denying access to people based on their sexual preferences.
Funding for schools that are religious is just simply wrong, one the grounds of discrimination, economics, and quality of education.