Do you mean co-education?
1.it makes environment where everyone is equal
2.it encourage girls to do better then boy in exam
3.it give free hand for girls
1.it emasculate boys.
2.only boys gets corporal punishment and girls get relaxation due to their gender (it is one type of discrimination)
3.boys indoctrine in such way that they feels guilty of what did with woman in past? ( thanks to communist and mis-andry ideology!