Most parents think smaller classes are wonderful. Most economists who have looked at the data think small classes might be good, but that reducing class size isn’t a terribly effective way to spend money. (In fairness, the evidence on the causal effect of smaller classes is pretty limited.)
Is there an interesting international pattern of class sizes that might shed light on U.S. class size? Basically, no. Class sizes around the world just don’t look all that different from class size in the United States, at least not in the subset of countries where we have good data.