Prince William County gives the SDMT to randomly selected 1st and 2nd grade students each Spring. The County began administering the test when Investigations was mandated county-wide.
PWC students continue to struggle with computational fluency in both Grades 1 and 2. Computational fluency is one of Investigations noted weaknesses and our students scores on the computation portion of the SDMT reflect that weakness.
For Grade 1, PWC student performance on the concepts and applications portion of the exam improved again this year. The overall percentage correct in 2007, 2008, and 2009 were 76%, 79%, and 80%, respectively. Accordingly, PWC’s national percentile rank for Grade 1 concepts and applications has also increased.
Our Grade 1 scores for computation did not fare as well. The percentage correct for computation for grade 1 students in 2007, 2008, and 2009 were 70%, 78%, and 70%.
PWC national percentile rank for Grade 1 remains slightly above average in the 54th percentile overall (56th for concepts / applications and 54th for computation). That means that PWC students overall did as well as or better than 54% of other Grade 1 students across the nation.
For Grade 2, PWC student’s scores for both both concepts / applications and computation declined. The overall percentage correct for concepts / applications in 2007, 2008, and 2009 were 89%, 92%, and 85%, respectively. The overall percentage correct for computation in 2007, 2008, and 2009 were 85%, 96%, and 83%, respectively.
Accordingly, PWC’s national percentile rank for Grade 2 in concepts / applications and computation were down as well. Unlike Grade 1, where the percentile rank for concepts / applications and computation are approximately the same, for Grade 2 there is a sharp gap between the national percentile rank for concepts / applications and computation.
The national percentile ranks for Grade 2 in concepts / applications in 2007, 2008, and 2009 were 54th, 62nd, and 61st respectively. The national percentile ranks for Grade 2 in computation in 2007, 2008, and 2009 were 45th, 47th, and 47th respectively.
This means that while our 2nd grade students perform above average nationally in concepts and applications, they perform below average nationally in computation.
Increases from Grade 1 to Grade 2
PWC claims that the increase in test scores from Grade 1 to Grade 2 is evidence of the success of Investigations, and scores from Grade 1 to Grade 2 do continue to increase. Students in 1st grade in 2007 and 2nd grade in 2008 saw their percent correct increase from 73% in 2007 to 90% in 2008. Students in 1st grade in 2008 and 2nd grade in 2009 saw their percent correct increase from 79% in 2008 to 84% in 2009.
However, PWC fails to mention that Grade 2 scores are consistently higher than Grade 1 scores, both in PWC and nationally. In 1st grade 70% correct puts you in the 54th percentile nationally, while in 2nd grade 83% correct puts you in the 47th percentile nationally. How much of the increase in the percentage correct from Grade 1 to Grade 2 can be attributed to Investigations versus the inherently higher scores in 2nd grade, is undetermined.
Because the SDMT has only been administered since Investigations was mandated, any conclusions about increases in student performance as a result of Investigations can not be substantiated. Unlike students nationally, PWC students continue to struggle with computational fluency. Without some sort of intervention, those struggles will only be further compounded as our children advance.