Abstract
Existing evidence implies that student achievement in year-round schools is either equal to or superior to that of student achievement in traditional calendar schools and that its positive effects may be particularly strong for disadvantaged students. However, most studies on this topic suffer from serious methodological limitations. The author sought to better examine achievement differences between year-round and traditional calendar students using 2 years of data from over 345,000 North Carolina public school students in Grades 3-8. Results indicated that achievement in year-round schools was no higher than in traditional calendar schools and that differential effects for certain student subgroups, although statistically significant in some cases, were not of practical significance.