Hello, I'm glad to answer your question. I think it is most important for children to learn mathematics, so that children can like mathematics and fall in love with it, and have a sense of accomplishment in mathematics class.

Then I know something about the four mathematical institutions you mentioned, all of which are brand institutions that do Olympic mathematics. Therefore, learning and thinking here, but Gauss doesn't say that it is mainly based on Olympiad, which is also quite famous, but it has its own characteristics, which can make children like mathematics from never. I think it's Zhibo Mathematics.

They mainly focus on children's interests, and have educational toys such as Rubik's cube, fast folding cup and nine-ring chain to attract children quickly, so that children are not so boring when learning mathematics knowledge points. I suggest you choose Zhibo Mathematics to try. Pure hand tour, give extra points.