iTunes U User Guide for web
Send a private message in iTunes U for web
To answer individual student questions, give a student extra help, or provide feedback on an assignment, you can chat privately with a student. Using a student assignment journal, you can send a message or document to the selected student in your private course.
You can also view the assignment journal in the Posts | Assignments pane. Click Posts > 
Assignments, click the assignment you want, then click a student discussion.
Chat privately with a student
In iTunes U
for web, click the course name in the dashboard for the course where the student is enrolled.Click Admin
, then click Grades.Click the progress cell for the student you want.
iTunes U displays the assignment journal for the student.
Enter a comment or question for your student, then click Send.
Click
, select a document to send to your student, then click Done.The maximum file size for each document you or your student uploads is 500 MB.
iTunes U sends your message to your student and updates the assignment journal with the new information.