As an instructor, you have the option to turn on email alerts so that you are notified each time someone signs up for one of your classes.
Here's how you can enable this feature so that you will receive email notifications for new students enrolled in your specific classes:
1) From your homepage click "Edit My Settings"
2) From the following page, scroll down to "My Notifications". You will see a check box next to "Send me an email whenever a new enrollment occurs in one of my classes". Click on this box and then click "Save" to enable this option.
Now you're all set to receive auto emails for new enrollments.