We have had to disable the Inbox messaging feature for everyoone as we can't disable it for students only. If we could have it turned on for students, we would want to be able to limit students messaging to/from teachers and coaches. We don't want students to be able to message other students.
There are quite a few similar ideas on here that need to be merged. This is necessary for all schools to be able to determine who can have access to messaging by student or grade level. There are kids that abuse this and we must have the ability to turn off their access.
This is exactly the reason why we have it turned off too. This feature would be extremely helpful if we can limit student messaging in this fashion and give parents similar limitations as well.