Although several studies have focused on why school climate is important, the timing of the collection of climate measures should be considered. This is of particular interest to schools that gauge school improvement efforts within a school year and are interested in how climate changes from the beginning to the end of the academic year. We show that there is a tendency for school-level climate measures to fluctuate in a predictable, nontrivial manner (ds = 0.25-0.47). Findings are based on data from 26 secondary schools (using over 20,000 student responses) that had school climate measures taken in fall and spring over 18 months. We show that in the fall, on average, students consistently had a more favorable outlook of the school based on five climate measures. [This is the online version of an article published in "School Psychology Review."]