I have heard that even a very good public school district is a year behind Germany (German parents reporting that). My kids are too young for me to be able to confirm or deny that. BUT when I went to college, both of my American roommates had to retake (and struggled with) high-school level Algebra, while I placed into multivariate calculus. In the more advanced math classes I took, there were no native English speakers - only foreign students and recent immigrants. While this was many years ago, I should mention that failing exams and having to repeat years of education was very common in my homecountry at the time(only 1/3 of my 5th grade class completed high school on time).
