My son is 11 years old. I have been sitting in on his lessons for many years. I take notes on the lesson, and help out with his practicing at home. Should I let him take lessons on his own, or keep attending his lessons?
I would say that the answer to your question is a very individual one. I have had parents observe lessons with me and take notes, as you mention doing, with children as old as 16. I have also had parents of children as young as 4 years old tell me that they thought their child would concentrate better if they waited outside.
One memorable instance was teaching violin in a group class setting at a school where one child’s parent, who was also a teacher at the school, was very enthusiastic and would come and sit in on her daughter’s groups violin class. Her daughter wanted to be like the other children, who had no parents in the class, and whose parents were not also teachers, but her mother really wanted to be there. Eventually, the daughter threw her mom out, and her mother was content to check in with me outside of class to ask how she could best help her daughter with practice at home.
My advice would be to check in with your son’s violin teacher, and then maybe have a brief check-in with your son to see how best to move forward!