Since the 1970s, the National Assessment of Educational Progress has monitored the academic performance of 9-, 13-, and 17-year old students with what have become known as the long-term trend assessments. In this report, both 9- and 13-year-olds scored higher in reading and mathematics in 2012 than students their age in the early 1970s, but 17-year-olds did not show similar gains.
