为何年少总是缺觉?(Why are Children Lacking Sleep?)

　　just how important is school nowadays? teachers often complain that homework is not done well and that students are often arriving at school delayed and yawning through lack of sleep.there are, it seems, two main explanations for this. firstly, many young children stay up late to watch tv programmes suitable for them, which may finish as late as 8:00. no child wants to admit not having seen what everybody else has.

　　secondly, a growing number of older children, particularly those approaching school-leaving age are taking up parttime evening or weekend work. they feel that working experience, not academic qualification will help them find jobs on leaving school. one can sympathize with both groups of children but it doesn't make a teacher's life any easier.