As if House and Senate conferees didn't already face enough difficulties in creating a fair definition of "adequate yearly progress" for the new ESEA, an article in this month's Washington Monthly explains how high rates of student mobility can doom an otherwise solid accountability system. According to a GAO study, one out of every six U.S. third-graders has attended three or more schools since entering first grade, and a New York Times investigation found that 40 percent of the students in a typical New York City classroom changed schools over the course of the year. Unless an accountability system has some way of dealing with highly mobile students, schools may be sanctioned for failing to educate kids who have barely spent any time on their premises. For more, see "Student Movement: The Fatal Flaw in the Bush Education Plan," by Thad Hall, Washington Monthly, September 2001, http://www.washingtonmonthly.com/features/2001/0109.hall.html