For teaching e mail can be used in the following ways:
E mail is useful for setting up appointment
People who want to see me know that easiest and most successful of contacting me via e mail
E mail is a good if you are trying to a range a meeting between several people .
E mail is useful for answering the more mundane sorts question that arise : question about reading ,assignment, problems with concept or practical work
Email can be used to send a message to whole group of students .use it to set homework assignment and students sent their assignment via e mail.
Finally,e mail can be used to have discussions between student . Everyone has the chance to participate and their massage can be sent to all members of the group.