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    You may like chewing gum (口香糖) after meals to stop your breath smelling bad; or your mother might use a special neutralizer (调理剂) to protect her permed hair (烫发). But have you thought about the chemical principles behind such everyday actions?

    On March 2, the Senior 3 students from the IB (International Baccalaureate, 国际文凭) classes at Beijing Huijia Private School presented their discoveries, all in fluent English. This kind of seminar is held every year to show the achievements of the IB chemistry experiment lessons offered by the school. IB is a qualification based on a common curriculum (课程) for students aged 16-18 in any country and is recognized by universities everywhere.

    "Once I saw an advertisement for xylitol (木糖醇) gum," recalled Zhang Xinju. "Suddenly an idea came to my mind: are there any chemical reactions when the xylitol is working on our teeth?"

    Zhang and his partner Bu Xuan visited several hospitals to try and find out. "Doctors know that xylitol can protect teeth, but few could explain how the chemical reactions happen," said the 17-year-old boy.

    Presenting the results of their research in English to an audience of Chinese and foreign judges was never a problem for the students.

    "Textbooks for IB students are in English, and our teachers speak in English," explained Wei Duan and Han Yu, whose research topic was "The Acid-Base Reaction (酸碱反应) in the process of Hair-Perming".

    "In Senior 1 we often referred to Chinese textbooks, but we found we could understand and express it all in English by the second year."

    Lu Jiang, the school's IB chemistry teacher and China's only IB vice-examiner, is proud that her students can apply scientific theories they learn in class to daily life.

    "You might have learned these facts from you kindergarten teachers, but few think about the theories behind them," Lu said. "This kind of practice is intended to develop the scientific thinking they will need in their future studies."

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    Explore the possibility of using the iPad App Store in the classroom.

    App Name: Bridge Constructor/Cost: $1.99

    Bridge Constructor lets players build increasingly challenging bridges over deep valleys, canals and rivers. Stress tests reveal whether the bridge kids build can withstand continual use from cars, trucks, and more recently, super-heavy tank trucks. Players can choose from among a range of bridge-building materials such as wood, steel, cables and concrete pillars (混凝土柱). Each bridge also has a budget, and there are numerous ways to successfully complete each challenge.

App Name: Pyramid Adventure 3-D/Cost: $13.99

    The interface allows users to fly around the plateau where the pyramids and the Sphinx are located at Giza near Cairo. Interactive, three-dimensional maps let students wander around the labyrinthine tombs and passageways. Uses can examine wall paintings in detail, or view royal statues and objects with a 360-degree feature. To help explain the world of ancient Egyptians, the app offers an accompanying interactive book, specially written by world-famous Egyptologist Zahi Hawass.

    App Name: Grammar Up/Cost: $4.99

    Grammar Up is a multiple-choice quiz system for English grammar. Kids and adults can learn most quickly when playing learning games with real-time error feedback, which Grammar Up provides. The app also offers students practice tests so they can see how much they've learned. A summary is presented at the end of each test, showing the time spent, a score, and the questions answered correctly and incorrectly. The results are also e-mailable.

    10 years after my parents got married, my dad went to work in the oil fields, and soon accepted a job working overseas. The money was great, but the fact that we only saw him every other month disappointed me. My mom stayed home with her five children, raising us alone. We had a place in the country with horses, dogs, chickens and a few head of cattle. Mom was very busy, but always made time for us. Of course, lots of mothers did things like that. But Mom's greatest achievement was yet to come.

    When the oil business declined(衰退) in the 1980s, my dad and most of his friends lost their jobs. The wives were at a loss to know how to manage without large monthly paychecks. But my mom was different. She helped out by working part-time jobs and she learned to drive a semi-truck, so she could help my dad make more miles at his new job. But with three teenagers at home, she couldn't spend time on the road with him, so he decided to find a different kind of job.

    Mom found an ad for the International Air Academy in Vancouver, Washington. She had always dreamed of working as a flight attendant but had chosen a family over a career. She was fascinated by the idea that she might be able to work in the travel field after all. Having no idea how she would pay for the schooling, or even if she'd get a job, she took a leap of faith(冒险一试) and dialed the number.

    It wasn't easy, but she passed the entrance exam and was admitted to the three-month training course. That was only half the battle, though, as she still needed the tuition. She finally got a loan( 借款) to cover some of the expenses, and the president of the school gave her a personal loan to cover the rest.

    As she read her welcome packet, she realized there was a strict dress code( 着装要求), requiring professional dress each day. This was not something she had. And she also needed to see an eye doctor. Her older brother sent her enough money to buy the clothes she needed and test her eyes. And then she took her two youngest － daughters my sister and me to Vancouver, where there was an apartment waiting for her in the family housing section.

    In the first day of class, she was so nervous. I can remember her taking deep breaths and trying to calm herself before leaving. She was forty-five years old, and that made it a little intimidating to walk into a classroom full of twenty-year-olds and try to hold her own. But she stood by her commitment and graduated at the top of her class.

    Her first job as a travel agent was with a large agency in Aurora, Colorado. She felt great about her achievement and proud of the beautiful high-rise building she worked in. I was so proud of what she had done. She'd found a way to rise above the curveball( 弧线球) life had thrown at her. Instead of quitting as many of her friends had, she charged ahead and created a brand new career.

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