Is it forbidden for a female students to free mix with males in the schools, colleges etc
The reason behind the prohibition against free mixing between men and women is due to fear of falling into fitnah, lest it becomes a means to committing lewd acts; (a means) to violating the honour of women and corrupting the society. And indeed these affairs can become a greater reality through free mixing in education. Therefore, it (free mixing in education) is forbidden.
[Fataawaa Al-Lajnah Ad-Daa’imah 12/169]