在上课开始之前。

Before the class would start.

youdao

另外一些学校只要小学生们不在上课时间使用，允许他们携带手机入校。但是多数学校还是希望孩子们在每一堂课开始之前，把那些电子装备暂时存放在储物柜中或收好在袋子里。

Others allow pupils to carry phones if they do not use them during the school day, but most expect electronic equipment to be deposited in lockers or put in zipped bags at the start of each lesson.

youdao

另外一些学校只要小学生们不在上课时间使用，允许他们携带手机入校。但是多数学校还是希望孩子们在每一堂课开始之前，把那些电子装备暂时存放在储物柜中或收好在袋子里。

Others allow pupils to carry phones if they do not use them during the school day, but most expect electronic equipment to be deposited in lockers or put in zipped bags at the start of each lesson.

youdao