http://pirls.bc.edu/timss2007/PDF/T07_M_IR_Chapter1.pdf
a chart of mathematics achievement levels in various countries. Although the United States is above the international average score among the countries surveyed, as we would expect from the level of economic development in the United States, the United States is well below the top country listed, which is Singapore. An average United States student is at the bottom quartile level for Singapore, or from another point of view, a top quartile student in the United States is only at the level of an average student in Singapore.
A thoughtful article from the Notices of the American Mathematical Society
http://www.ams.org/notices/200502/fea-kenschaft.pdf
identifies some of the problems with United States education that hold back full expression of the learning potential of many Americans. Professor Hung-hsi Wu of Berkeley has devoted much of the last decade to writing important articles about what needs to be reformed in United States mathematics education.
http://math.berkeley.edu/~wu/Lisbon2010_4.pdf
http://math.berkeley.edu/~wu/Lisbon2010_2.pdf
http://math.berkeley.edu/~wu/NCTM2010.pdf
http://math.berkeley.edu/~wu/NoticesAMS2011.pdf
http://math.berkeley.edu/~wu/CommonCoreIV.pdf
Other mathematicians who have written interesting articles about mathematics education reform in the United States include Richard Askey,
http://www.aft.org/pdfs/americaneducator/fall1999/amed1.pdf
http://www.math.wisc.edu/~askey/ask-gian.pdf
Roger E. Howe,
http://www.ams.org/notices/199908/rev-howe.pdf
and
James Milgram.
ftp://math.stanford.edu/pub/papers/milgram/milgram-msri.pdf
ftp://math.stanford.edu/pub/papers/milgram/report-on-cmp.html
All those mathematicians think that the United States could do much better than it does in teaching elementary mathematics in the public school system. I think so too after living in Taiwan twice in my adult life (January 1982 through February 1985, and December 1998 through July 2001). Taiwan is not the only place where elementary mathematics instruction is better than it is in the United States. I'm trying to do my part to fix the problem of United States elementary mathematics education by offering supplementary classes in elementary mathematics on weekends through my start-up, a nonprofit organization. My colleagues and I are gratified to have clients commute in for the classes from eight different counties. The client children have parents who grew up in the United States and also Ghana, Korea, China, India, Pakistan, Russia, and other countries. All the families want to make sure that their children have a chance to succeed in the next generation.