From the selections at the bottom of the page, cllick and you'll see

If you click on words "All students" you'll see a list of the students in your class with their email addresses. To send email to all or to some students,click the to the left.

Note: the students on this mailing list are only the students who have logged in at https://classes.yale.edu/student and chosen your class. This may not be the same as the list of students who are listed by the registrar.

This mailing list can be used only by the instructors of the class. If you wish to have a mailing list that can be used by all students, please request a pantheon mailing list.

Hint: To save time and effort you could copy and paste the email addresses from the list on the classes server to your pantheon list.

The only way to remove a student from the list is to ask the student to log in to the classes server and delete the course.