Laramie County School District One Superintendent Mark Stock says a recent study of fifth grade reading test scores in the district shows that students who changed schools usually scored lower than those who have not moved. Stock says 94 percent of fifth grade students who had gone to only 1 elementary school throughout their school years received a grade of ''proficient"  on the tests. Students who had moved once scored proficient around 70 percent of the time, while students who had moved twice typically received scores of proficient somewhere around 60 percent of the time. Stock says even more frequent moves continued to show lower test scores. He says since poverty was eliminated as a factor by the survey process, the obvious conclusion is that frequent school changes have a negative impact on student's education.