From the class roster, teachers are able to use the "Send Communication to" button to message students, parents, or all. This button only works if the today's date is within the academic term of that class. For example, our semester starts tomorrow, and when teachers navigate to their next semester classes to beging getting ready for the next term, teachers are not able to message students about an important assignment until tomorrow comes. It is not possible/desireable to start 2nd semester in Core setup before 1st semester ends.
Overall it would be a helpful feature for any teacher to message any student. We have tutors and other staff members who need to communicate with students and we'd like to do this communication through the Blackbaud messaging funcationality rather than email.