When Do Most U.S. Schools Begin? August or September?

At this time of year, many journalists and bloggers write about the once obvious fact that schools used to begin in early September, the traditional start time for U.S. schools for nearly a century. In 2023, however, about 70 percent of nearly 50 million public school children were already attending classes by mid-August. A few writers (and parents also) sometimes ask why the date for the end of summer vacation keeps creeping backward (see here and here). Answers to this question often cite increased teacher efficiency (more time to prepare students for standardized tests). Other answers mention having a less hectic closing of the first semester of the school year before Christmas break and getting out of school in late May which then reduces graduating seniors’ shenanigans in last few weeks of school. All of that tinkering with the school calendar still preserves other vacations during school year such as in mid-February and April for the Easter holiday. Such talk about opening…