24-hour notice for canceling a lesson is by far preferred! 
Please do your best to let me know 24 hours in advance if you can’t make the lesson.  
However, I do understand that last minute problems do crop up.  
So, as long as I get a PHONE CALL/PHONE MESSAGE by 10:30 the morning of the lesson, you will not be charged for the lesson.  
This gives me a little leeway to rearrange my schedule and perhaps fill in your spot with another student.   
If you call after 10:30, you will be charged for the missed lesson. 

I look forward to working with you (and/or your children) on your/their musical goals and aspirations 
~ and thank you for your understanding!  I appreciate your business very much!