Cyrus123,
I guess you have to tell him to read the fingering from the score. You may help him if you read the book, there will usually some gulidlines on how to play the music in the top or bottom part of the pages, and those were usually missed during the lesson (or I should say most teacher won't go though those important information). From my experience, all good music player's parent will involve actively when their children are very small!
Maisyraymond,
Digital piano is not really good starting from grade 2-3, in a younger age it would help developing practises and reading score, but once you have to learn controlling fingers, you still have to have a "REAL" piano. If you are just considering the price, why don't consider 2nd-hand? Any of good functioning piano would be playable for grade 8 already. Even the cheapest brand new one in Tomlee, spend you less than $10K, could help also.
Indeed, digital piano is not cheap, even more expensive than a 2nd-hand. If you are looking for those which can capable to a real piano, they would spend you more than $30K!
If you need help in searching 2nd-hand piano, let me know.
Music is the art of thinking with sounds.
–Jules Combarieu