Raeann Sleith began making bracelets (手链) when she was six. Family and friends loved her designs and asked for more. When admirers suggested that Raeann sell her bracelets, she realized she wanted to do just that — and donate the money to help kids with special needs, like her brother Derek.

    Raeann's older brother, Derek, has cri du chat syndrome. Children with cri du chat usually have problems understanding ideas and might have a hard time learning to talk. Many also have weak muscles that can cause problems with walking or using their fingers to pick things up. The term cri du chat means “cry of the cat” in French. Babies with cri du chat often have a high-pitched cry that sounds like that of a little cat.

    Over the years, Derek's teachers helped him learn sign language and gestures. They also taught him skills such as recognizing letters, cutting with scissors, and understanding basic math. Raeann wanted to donate money to Derek's school. “I just wanted to help my brother,” she says, “and the people who help him.”

    At first, Raeann focused on creating jewelry that would raise awareness for cri du chat. But people started requesting bracelets to wear as a symbol of support and awareness for a variety of other diseases and disorders. To create those symbols, Raeann researched the color most often associated with raising awareness for the disease or disorder, such as pink for breast cancer or orange for leukemia.

    In the end, it turned out to be a great idea. In only a few years, Raeann has donated more than $30,000 to local charities. Raeann's mom says that working on the bracelets has developed the generosity and kindness that already existed in her daughter. Raeann plans to keep making bracelets and raising dollars for charities. “I just want to keep going on with it,” she says, “to help my brother more.”

    The human brain remembers negative experiences more easily than positive ones. Our brains have developed this way because threats, like dangerous animals, had a more immediate effect on our ancestors' survival compared to positive things like food or shelter. As a result, you likely know what makes you unhappy, but do you know what makes you happy?

    Research suggests that our level of happiness depends partly on factors we cannot control—our genes and our life circumstances. But our level of happiness is also shaped by the choices we make. If you've been chasing wealth, fame, good looks, material things and power, you may be looking for happiness in all the wrong places. Psychologists suggest that the following habits make people happier.

    People who form close relationships tend to be happier than those who do not. The number of friends we have is not important. What matters is the quality of our relationships. Relationships that bring happiness usually involve the sharing of feelings, mutual respect, acceptance, trust and fun.

    People who exercise regularly improve both their physical and mental well being. Some research has shown that exercise can be as effective as medication in treating depression.

    When we are so interested in an activity we enjoy that we lose track of time, we are in a state of flow. The activity could be making art, playing piano, surfing, or playing a game. People who experience flow in their work or hobbies tend to be happier.

    People are more likely to be happy if they know what their strengths are and use them regularly, People who set goals and use their strengths to achieve them tend to be happier. People are especially happy when they can use their strengths to serve the greater good.

    People who think positively by being grateful, mindful and optimistic are more likely to be happy. Being grateful means being thankful, Bejing mindful means being open to, focusing on and enjoying the experiences of the present moment. Being optimistic means being hopeful about the future.

    Teachers say the digital age has had a good influence and a not-so-good influence on this generation of American teenagers. More than 2,000 middle and high school teachers took an online survey. Researchers also spoke with teachers in focus groups.

    Three-quarters of the teachers said the Internet and digital search tools have had a "mostly positive" effect on their students' research habits and skills. But 87 percent agreed that these technologies are creating an "easily distracted generation with short attention spans (持续时间)". And 64 percent said the technologies "do more to distract students than to help them academically(学业上)". Many students think "doing research" now means just doing a quick search on Google.

    The Pew Internet Project did the survey with the College Board and the. National Writing Project. Most of the teachers came from Advanced Placement classes, which provide college-level work for high school students.

    Judy Buchanan is director of the National Writing Project and a co-author of the report. Ms. Buchanan says digital research tools are helping students learn more, and learn faster. Teachers really welcome these tools because they are ways to make some of learning exciting and engaging. Young people welcome these tools. And the goal is to really help them become creators of content, and meaningful content, and not just sort of consumers.

    But one problem the survey found is that many students are lacking in digital literacy. In other words, they trust too much of the information they find on the Internet. Another problem the survey found is blamed on something that might not seem like a problem at all: being able to quickly find information online.

    Teachers say the result is a reduction in the desire and ability of their students to work hard to find answers. They say students are depending too much on search engines and do not make enough use of printed books or libraries. Many teachers are also concerned that the Internet makes it easy for students to copy work done by others instead of using their own abilities.

    How many men do housework? Recently a European commission (委员会) tried to find out people's ideas and reactions to the women's movement. As part of their survey, they asked many men and women the question, “Who does the housework?” The men answered very differently from the women!

    The housework they asked people about was: preparing meals, washing dishes, cleaning the house and babysitting. 48% of British husbands said they did these things. 37% of Danish (丹麦的) men helped in the house. But only 15% of Italian men said they did the housework; many of them said they never helped at all!

    But there was an interesting point of view from the wives. According to British wives, only 38% of their husbands helped in the house. And Italian wives said that their husbands hardly ever helped. The Italian and British men did not tell the truth! The Commission found that Danish men were the most truthful husbands; their answers were the same as their wives' answers.

    Do the men you know help in the house? Do you think the survey gives a true picture in your experience? Write and tell us what you think.

    Put an ice cube from your fridge into a glass of water. You have a piece of string (线) 10 centimeters long. The problem is to take out that piece of ice with the help of the string. But you must not touch the ice with your fingers.

    You may ask your friends to try to do that when you are having dinner together. There is a saltcellar on the table. You must use salt when you carry out this experiment.

    First you put the string across the piece of ice. Then put some salt on the ice. Salt makes ice melt (融化). The ice round the string will begin to melt. But when it melts, it will lose heat. The cold ice cube will make the salt water freeze again.

    After a minute or two you may raise the piece of string and with it you will raise your piece of ice!

    This experiment can be very useful to you. If, for example, there is ice near the door of your house, you must use very much salt to melt all the ice. If you don't put enough salt, the water will freeze again.

    Microsoft PowerPoint is the world's most common presentation tool. It emerged from software company Forethought Inc in the 1980s. Bob Gaskins was the man behind it.

    "I knew in the early 80s that there were as many as a billion, a thousand million presentation slides being made per year just in America," Gaskins says, but they were all made by hand and almost nobody was using computers to do them.

    "It was clear to me that here was a huge application worth billions and billions of dollars a year that could be done on computers as soon as there was a revolution in the kinds of computers that we had."

    Gaskins was onto something, but it was a hard sell at the time. The software wouldn't run on any existing personal computers. Anyone wanting to use it had to buy a new machine. Even so, people bought personal computers for the first time in order to be able to use PowerPoint, says Wired magazine journalist Russell Davies.

    Davies explains that before PowerPoint, people used slides to convey information to groups — but anyone creating a presentation had to send away to get their materials made. It took a long time to do, was difficult to make changes and because it was so expensive, only the most senior people in an organisation got to do it.

    "PowerPoint," Davies says, "made it possible for everyone in an organisation to stand up and say their piece."

    PowerPoint has helped turn us all into presenters — but it' s also been accused of over-simplifying ideas and distracting (干扰)us from clear thinking.

    Sarah Kaplan is a management professor at the University of Toronto's Rotman School of Management. She has noticed that, rather than people asking for new analysis or insights in meetings, they were asking for more PowerPoint slides.

    Kaplan says that some CEOS, such as Amazon's Jeff Bezos, have banned its use. "He felt, and I think many people feel, that PowerPoint became such an object of the process that they lost the ideas inside of it and that is the risk."