[Inbox] Email (message) multiple classes at one time

Instructors often want, or are asked, to share news and information of importance to all our classes.  Currently, that means copying and pasting that information into anywhere from 2-5 different classes.  Given that there is a drop down box for choosing a class to message currently, adding the ability to select multiple classes seems like it would be an easy "fix".  Please add this capability ASAP.