That’s not really true (about Asians). If you look at, say, the Hmong population in Minnesota, or the Burmese population where I currently live, they are less successful academically than average. Everyone loves to talk about “Asian culture” as a reason for Asian-American academic success, but it’s way overstated. The main reason Asians are successful is simply that a large portion of us are children or grandchildren of immigrants and immigration to America (aside from poor refugees) selects from the highest socioeconomic strata of foreign countries.

Edit for sources: for a general overview of what causes immigrant success in America I recommend Boustan and Abramitzky’s recent book, Streets of Gold. I also like Ed Lazear’s paper on the nuts and bolts of selection in America’s immigration system, but that’s a bit technical.