The study of music is a performance art. Each one of us learns as we play. Some of the playing can be done in the lessons with our teacher, and some can happen as we collaborate with others, perhaps in duets or school groups. Pianists have a whole array of sounds at their fingertips. We can make harmony entirely on our own, unlike other instruments of the orchestra and band. However, we also need to sit down alone and play (practice) regularly to make the progress that allows us to flourish at the keys. Below are a few links about how to become fluent at the art of practising.
August 28, 2014: 1) Here is a YouTube link to someone talking about how to "Get in the Zone" in practicing. Perhaps this point of view will help you in your practice journey.
Below is a blog from Teach Piano Today, a duo of BC teachers who have some very innovative ideas. If you're unsure of what to say while you're child is practicing to encourage them, I have a sheet of suggestions you can ask for. You can also use the printout included in the blog below by printing it on Avery 5160 stickers.