the broad outline of the school mathematics curriculum in the united states was set about hundred years ago. grades K-8 were devoted to arithmetic,grade 9 was algebra,grade 10 was geometry,and grades 11 and 12 included another year of algebra,solid geometry,and trigonometry. At that time,one hundred years ago,only about half of an age cohort was in school at grade 9,and those in high school tended to take a year or two of mathematics at most.usually only future engineers and scientists took mathematics beyond grade 10.