Here are the different types of SMS features than can be enabled in your account: 

Texting Allowed: Enable this if you'd like to send SMS messages/reminders to the student. If disabled, My Music Staff will not allow you to send SMS messages to them. 

Send Reminder Texts: Enable this if you'd like this individual to be able to receive SMS reminders for lessons/events. 

Send SMS invoice notifications and reminders: Automatically sends SMS notifications for emailed invoices, invoice payments and overdue invoice reminders. When enabled, the student's primacy contact with a listed "Mobile Number" will receive these SMS notifications.