You can send message to many persons in different classes. We suggesting you to follow these simple steps

Step 1: Go to EduNiv admin page

Step 2: Go to message module and type content of message in text box

Step 3: Click on address book, which is adjacent to roll number 

Step 4: In that select class, now you can able to see the name list 

Step 5: Now you can select students name, after that click on add selected students 

Step 5 : Just close address book and send message to selected students