4 year old, 15 min attention span is good. practice 5 min a day
increase to 30 min class after 5 year old, practice 15 min every day.
then 6 year old, 45 min class, practice 30 min every day.
increase to 30 min class after 5 year old, practice 15 min every day.
then 6 year old, 45 min class, practice 30 min every day.