Math LD: Identifying Basic Number Processing Difficulties - NCLD.
Many elementary and middle school students find math challenging, but an estimated 5 to 9% experience difficulties severe enough to be categorized as having a mathematical learning disability (MLD). An emerging consensus, at least among researchers, is that such students must exhibit comparatively poor performance on a standardized mathematics achievement test (at or below the 10th percentile) over at least a successive two-year period to be properly identified as having MLD (also known as dyscalculia). As a consequence, children who meet such criteria are typically not identified prior to first grade. And while research in this field is at least 10 years behind research on reading disabilities, progress is being made
