The below quote is sobering, considering this is the average student.
The average student in many of the top-performing countries graduates two to three years ahead of the average high school graduate in the United States. The distance between what our high school graduates know and can do and what their high school graduates know and can do has been steadily widening in recent years.The problem with the NAEP scores is not that they just slipped a bit. It is that those scores are pretty much the same at the high school level as they were 40 years ago. During those 40 years, one nation after another has surpassed our performance. That is the disaster on which we should be focusing. What it says is that there is something deeply wrong with our whole system of education and it has got to get fixed.