What is the ruling on teaching male and female university students at the same time, and is it permissible to communicate with them via social media platforms such as Facebook and others?

Mixing (between genders) in universities is an abomination that brings calamities upon society and opens doors to corruption and discord. The original principle is the segregation of sexes in education. However, if there is a need to study or teach in mixed universities, it is permissible, provided Islamic guidelines are observed. It is also permissible to add some students to communication programs and converse with them about study matters when necessary, provided there is no fear of temptation and it is limited to the extent of the need. It is preferable to avoid this as much as possible.