Note that the tabs to navigate within your course have moved to the left side of the screen.
Also, note the new tab Rubrics, which allows you to post the rubrics for assignments in an easy-to-locate place. Check out the Populi blog post here.
Emailing all students in one course or section
You have a few options for emailing all the students in one of your sections or courses.
On the course Dashboard tab, click Email this section to email all enrolled, incomplete, and auditing students in this section of the course.
Selected Students on a Roster
On the course Roster, click Actions and select from your options:
Emailing any individual student
To email an individual student:
You can do this for any of your current students. However, if a student is not enrolled in or auditing one of your courses, you can only email him if his email address is set to Public.