Hua middle school mathematics textbook, Jilin Education Press, I think this is quite good. My children are also learning olympiad. She is not studying this textbook, but studying the series of primary school mathematics activities in the new century, published by Beijing Normal University Press. This is relatively simple. But I still like the one in China. Since the first grade, I have taken her to visit the Chinese school, and now I read the textbooks of the Chinese school at home by myself.