Since the 1970s, the National Assessment of Educational Progress (NAEP) has monitored the academic performance of 9-, 13-, and 17-year-­old students with what have become known as the long-term trend assessments. Four decades of results ofer an extended view of student achievement in reading and mathematics. Results in this report are based on the most recent performance of more than 50,000 public and private school students who, by their participation, have contributed to our understanding of the nation's academic achievement.