Guangzhou Art Museum, Children's Palace and Shu Hua Art Center are all good places for summer vacation. If you want to learn indoor hand painting, you can go to Shu Hua, which is famous. You'd better consult Shu Hua Customer Service for the price. I'm not sure about the details. You can find Shu Hua's homepage through Baidu Shu Hua Art. In terms of management, I'm afraid you will say that Shuhua is too strict.

PS Shu Hua's sketch is totally worth learning.