I was 12 when I came to Maywood School three years ago. Like most schools in the USA, classes here began at 8:00 a.m. However, the headmaster, Mr. Bergman, found there was a problem -- so many students were either missing the first class or arriving late. My Classmates and I often found it hard to keep our eyes open in the mornings, so lessons were no fun for us. Our grades weren't good either.

    In the end, Mr. Bergman asked the school doctor for advice. The doctor said that because teenagers' bodies are growing so quickly, they need more sleep than adults (~). But their body clocks make it hard for them to go to bed before 11:00 p.m., so the best time for them to wake up is around 8:00 a.m.

    Mr. Bergman decided to do an experiment (实验). He changed (改变) the start time for classes to 9:00 a.m. The school still opened at 8:00 a.m. and teachers used the extra (额外的) hour to prepare lessons.

    I didn't think the new timetable (时间表) would make much difference, but I was wrong. I felt much better! Everyone's grades improved. Also, more students had time for a hot breakfast together in the dining hall. We all felt healthier and happier.

    After three months, Mr. Bergman asked teachers, students and parents if they wanted to keep the new timetable. Everyone did.

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