After decades of what seemed to be an inexorable upward path, the number of students classified as learning-disabled declined from year to year over much of the past decade--a change in direction that is spurring debates among experts about the reasons why. The percentage of 3- to 21-year-old students nationwide classified as having a "specific learning disability" dropped steadily from 6.1 percent in the 2000-01 school year to 5.2 percent in 2007-08, according to the most recent data available, which come from the U.S Department of Education's 2009 Digest of Education Statistics. The decrease in the category goes hand in hand with a decrease in special education enrollment overall, though that change is not as large. Scholars say the dropping numbers could be linked to improvements in reading instruction overall; th adoption of "response to intervention," which is an instructional model intended to halt the emergence of reading problems; and a federally backed push toward early intervention with younger students before they're labeled.