This argument is known throughout the world. Both mother and father must spare time for the child; you can talk to the kindergarten, school and friends. Moreover, you can request the grandparents to take time and talk to children about this topic. I know the children may not have time as they are fully occupied with their home works and other activities. Spending 30 minutes twice in a week will help you a lot to learn about your food. Where there is a will there is always a way.