What is the ruling regarding mixed-gender group photos of university students, both male and female, that are hung and distributed?

The preponderant opinion is that a woman's face is 'awrah (i.e., a part of the body that must be covered), and this is sufficient to prohibit taking pictures that show women's faces or bodies, in addition to the fact that such intermingling opens the door to corruption. This is regardless of the scholarly difference of opinion regarding the permissibility of photography when there is no need for it.