each new school year brings fresh reminders of what 试卷、教案、课件、论文、素材及各类教学资源下载，还有大量而丰富的教学相关资讯！" type="#_x0000_t75">educators call the summer learning gap. some call it the summer learning setback（退步）. simply speaking, it means the longer kids are out of school, the more they forget. the only thing they might gain is weight.
most american schools follow a traditional nine-month calendar. students get winter and spring breaks and about ten weeks of summer vacation. some schools follow a year-round calendar. they hold classes for about eight weeks at a time, with a few weeks off in between. the national association for year-round education says there were fewer than three thousand such schools at last count. they were spread among forty-six of the fifty states.[
