What are the views of Hanafi, Maliki and Shafi'i (optional: 12er and 5er Shia positions) scholars who reside in Non-Muslim Countries concerning attending mixed classes in Secondary School? And I'd prefer opinions from people who are aware of the situation in diaspora because it really makes a difference.
In my country (Switzerland), there are no public Girl's and Boy's schools. The only alternative would be to attend schools run by Catholic institutions. Those schools have obligatory Catholic prayers and Catholicism is not compatible with Islam in many points (although Catholic positions are closer to Islam than laicist, libertarian or nationalist positions).
Given that, I usually recommend to attend mixed schools rather than confessional Catholic schools, stating that mixed schooling is allowed although not recommended. I am not sure to what extent this is supported.