It might be a good idea to move the view as teacher-student-guest switch to the sidebar on the left hand.
When you're editing the planner and you want to view the planner as an student you first have to go back to the course dashboard before you can toggle the switch. It would be more practical to be able to switch from the sidebar because it is always visible.
see the image I included, ofcourse the view as menu should be collapsed in my image.
after the back to school update this autumn the student view and the teacher view are so alike that there should be no need for the old teacher-student-guest switch. Please have a look at the attached example from the course overview page. Teachers have post and edit rights that students don't have. Students have a Task menu and teachers a Follow-up tasks menu. The rest of the two views are alike.