Do equations and historical( 历史的) facts give you a headache? A change in the school timetable(课程表) may be the cure.

    This  suggestion  is  based  on  a  recent  study  carried  out  by  scientists  from  Royal  Holloway, University of London, the UK. They found that teenagers could get higher marks in math if they studied in the mornings and better grades in history if they were taught in the afternoons.

    The researchers studied students' grade reports, class timetables and absence rates( 缺席率) at a middle school in Bulgaria over nine years. The results showed that when teenagers had math classes earlier in the day, they scored about 7 percent higher in tests than when taught in the afternoon. Lower-ability students feel stressed most when they were studying math in the afternoon. In history, students taught in the afternoon scored about 6 percent higher than when they were taught in the morning. However, there was no sign that similar patterns( 模 式 ) work for other subjects such as languages or geography.

    Velichka Dimitrova, who did the study, said the findings show that we perform( 表 现 ) better at different times of the day. “In the morning, our brains are better and fresher, so we are better at doing something like problem solving, where we require more speed and attention” Dimitrova told The Telegraph. “In the afternoon, it seems that this process slows down. On the other hand, history is more suitable for the afternoon, when we are more creative and open to discussion,” she said. Subjects such as foreign languages require both memory and creativity. This is perhaps why the time of day had no influence on language learning.

    Time-of-day influences such as these are believed to have something to do with the body clock.

    This is the system in our bodies that controls when we need to sleep. Some schools in the US and UK have tried later school starting times for teenagers, whose body clocks change as they grow into adults. Dimitrova believes schools should jump at this chance to improve their students' performance just by changing their timetables.

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清欢

      ①一千年前，苏东坡被贬黄州，曾与友人共游南山。友人以山中野菜招待，对此东坡诗兴大发：“人间有味是清欢。”想那苏东坡，虽然后半生颠沛流离，屡遭贬谪，但他不以物喜，不以己悲，一生追求清欢的人生真味，的确是把握住了人生的真谛，

      ②清欢，是清淡的欢快、清雅的欢愉，是“野渡无人舟自横”的悠闲自在、“行到水穷处，坐看云起时”的超然洒脱。清欢更是一种至高的人生态度和精神境界。

      ③日本学者写了一本《清贫思想》，他建议人们采取清贫的生活方式，淡化对名利、地位、权力的追逐，追求一种内心丰盈美好的恬淡生活。美国人普兰特的《简单生活》认为，简单生活是“表现真实自我的有明确意义的生活”，是“丰富、健康、和谐的生活”。清贫思想也好，简单生活也罢，提倡的都是清欢。

      ④其实中国人对清欢的提倡由来已久。早在两千多年前，孔子就对弟子颜回赞不绝口：“贤哉，回也！一箪食，一瓢饮，在陋巷，人不堪其忧，回也不改其乐，贤哉，回也！”面对困境，别人难以忍受，颜回却乐此不疲，欢而不改，这需要多高的境界、多深的修养呀。孔子对“在陋巷”却“不改其乐”的颜回连叹“贤哉”，这是老师对学生的高度评价，也是古代圣贤对清欢精神的高度肯定。

      ⑤人生苦短，生活的表象多姿多彩，其内涵却纷繁复杂。只要尽心尽力担负起自己的责任，做好自己该做的事情，就全然不必为烦琐之事烦恼。将自己的脚步放慢一点，放轻一点，过一种简朴的生活，享受一下世间原有的简单和真纯，追求精神上的愉悦，这样的快乐是永久的快乐。

      ⑥但是，在这纷纷扰扰的世界里，不是所有的人都能经得起名利的诱惑，鸡鸣狗盗者有之，蝇营狗苟者有之，蚕食鲸吞者有之。结果如何呢？这些追名逐利者或惶惶不可终日，或“反误了卿卿性命”，君不见有多少“苍蝇”落地，又有多少“老虎”进笼？他们的人生何乐之有？

      ⑦提倡清欢，并不是倡导“穷欢”，不是要我们走进深山老林，拒食人间烟火；崇尚清欢，也不是推崇“清闲”，不是要我们碌碌无为，得过且过。追求清欢，要不为世俗所困，不为名利所惑；要不断丰富自己的精神世界，勇于承担自己的责任。像苏东坡那样，虽遭受打击排挤，也不忘情于山水，而是为官一任，造福一方。

      ⑧清欢，人生的真味，做人的真谛，让我们用一生追寻。

                                                                                                                                                                     （根据袁浩文章改写）