Nagging Your Child To Practice Won't Work
Nagging your child to practice piano won't work. I have news for you. There's something called the Battle of the Piano and you've already lost if you have to nag your child. The Battle of the Piano is the time honored process whereby a child is either deemed a success at the piano or not.
Some children make it. They number 10% of all kids who try. Some children don't make it. They number 90% of all the kids who try.
Repetition Is A Very Dull Tool To A Child
The moment your child's interest in piano lessons starts to wane, usually due to a lack of creativity on the teacher's part, you have entered the Battle zone. First comes the "honeymoon," where a child finds piano rather fun and interesting. Then there comes a moment of reality, when the child realizes subconsciously that the teacher has no tools other than repetition. The one tool of the non-creative piano teacher is repetition, mindless and numbing, because it is easiest for these teachers to go page to page in a standard text.
Such repetition is fine for an adult who is determined to play Beethoven, and is willing to pay the dues to do so. But for a six year old, it is a crushing regimen, a fact borne out by the 10%-90% statistics. When a child's interest in the piano wanes, they are surely headed for quitting if the teacher's only tool is repetition. For this reason, find a creative piano teacher who knows how to deal with kids.
The Child Can't Blame You
As your nagging increases, the child becomes more and more alienated from the piano, until subconsciously the child blames the piano for your nagging. They can't hate you for nagging, you're Mom, so they hate the piano instead. Mind you, all the while you're unknowingly paying this teacher to make your child hate the piano, and you're adding to the stress with your entreaties.
The Teacher Blames The Child
You ask the teacher for advice, after all, you're paying them. I guarantee you their only suggestion will be that the child practice more. That's the one tool they have. It's as if your child hates broccoli, and the chef's solution is to serve even larger portions. That chef knows nothing of child psychology and human nature. Or cuisine. Look at it from the child's point of view.
This crossfire of negativity from you and the piano teacher can have only one inevitable result, and that is the emotional destruction of the child's desire to play.
A Difficult Problem Created By The Teacher
Nagging won't help. Nagging is a huge part of the problem, not the solution. The child simply follows human nature. What is the solution? A rule of thumb is to listen to your child. Don't think that going and observing a lesson will be any indicator of your child's progress. The teacher, your employee, will be putting on a performance and your child will be terrified that you will be displeased.
Listen To Your Child
Let the lessons continue for a few weeks and see if it gets better. Keep listening to the child and ask them how they feel about it, and be a sympathetic listener. Draw them out on exactly why they don't like it. Assume they might be correct. Get them to describe the lesson, perhaps request a comical reenactment. Put them at ease and make them give you more details. You're on their side. Then, if the child's attitude persists or gets worse, you have two choices.
End It Or Fix It
First, try a different piano teacher. Spend your time talking to local people and find out if there is someone who specializes in children. You need a teacher with a reputation for making music fun for your age group. Find out which teachers are disciplinarians and avoid them, especially with younger kids. The only other alternative is to give in to the child, and let them quit. It may actually be a better solution than allowing the bad feelings in the lessons to continue. Try a different instrument, switch to guitar, trumpet, drums, anything.
Or take a break from lessons and try again later when you're sure a better teacher can be found. Find out what things the child finds fun about musical instruments. Go to a store and try out musical instruments. Let them try a variety of instruments until they find one that suits them, and at which they seem comfortable and willing to expend at least a reasonable amount of effort.
Music lessons for children should be an enjoyable experience, and if it's not, there's something wrong. The number one rule is to never force a child to learn music. Ever. If you force them to play the piano, I guarantee you they will end up hating it.