Hello, my friend, for the children's art training class, you don't need to pay special attention to some education and teaching methods now. First of all, you should set a general direction for your training class. Next, you can go on better.

Children aged 4-6 can be classified as elementary classes. We should teach them the simplest stick figure, don't limit their creative talent, and cultivate their habit of doing more things with their hands and brains (this is not ADHD).

6~9 years old can be classified as an intermediate class, and they should be taught the concepts of stick figure and sketch. Don't be too anxious to teach them the basics of sketching, because this age group is not suitable for accepting the basics of sketching. You can also give this intermediate something.

9~ 12 years old can be classified as an advanced class. These children should teach them the basic theoretical knowledge of sketch and the basic exercises of sketch. How to teach them? I think you have started your class, so I don't need to tell you.

Above, I have set a general direction for you. I hope it can help your training class.