Most American students go to traditional public schools. There are about 88, 000 public schools all over the US. Some students attend charter schools.

    Charter schools are self­ governing. Certain companies operate some charter schools. They are similar in some ways to traditional public schools. They receive tax money just as other public schools do. Charter schools must prove to local or state governments that their students are learning. These governments provide the schools with the agreement called a charter that permits them to operate.

    Charter schools are different because they do not have to obey most laws that govern traditional public schools. Each school can choose its own goals and decide what to teach and how to teach them in their own way. Class size is usually smaller than in traditional public schools.

    The government strongly supports charter schools as a way to re­organize public schools, which are failing to educate students. But some education unions are against charter schools. One teachers' union has just released the results of the first national study, which compared the progress of students in both traditional schools and charter schools.

    The results of the study show that charter school students performed worse on math and reading tests than the students in traditional public schools.

    Some experts say the study is not fair because students in charter schools have more problems than students in traditional schools. Other education experts say the study results would make charter school officials realize that they should help their students make greater progress .

    More and more people like bicycling and it is no surprise. It is fun, healthy and good for the environment. Maybe that's why there are 1.4 billion bicycles and only 400 million cars on roads worldwide today. Bikes can take you almost anywhere, and there is no oil cost!

    Get on a bicycle and ride around your neighborhood. You may discover something new all around you. Stopping and getting off a bike is easier than stopping and getting out of your car.

    You can bike to work and benefit from the enjoyable exercise without polluting the environment. You don't even have to ride all the way. Folding (折叠) bikes work well for people who ride the train. Just fold the bike and take it with you. You can do the same on an airplane. A folding bike can be packed in a suitcase. You can also take a common bike with you when you fly. But be sure to look for information by getting on airline websites. Not all airlines are bicycle-friendly to travellers.

Health Benefits of Bicycling:

    It helps to prevent heart diseases.

    Bicycling helps to control your weight.

    A 15-minute bike ride to and from work three times a week burns off five kilos of fat in a year.

    Bicycling can improve your mood (心情).

    Exercise like bicycling has been shown to make people feel better, more relaxed and self-confident.

    Bicycling is healthier than driving.

    Close your eyes for a minute and imagine what life would be like if you had a hundred dollars less．Also imagine what it would be like spending the rest of your life with you eyes closed．Imagine having to read this page, not with your eyes but with your finger-tips．

    With existing medical knowledge and skills, two-thirds of the world's 42 million blind should not have to suffer．Unfortunately, rich countries posses most of this knowledge, while developing countries do not．

    ORBIS is an international non-profit organization which operates the world's only flying teaching eye hospital．ORBIS intends to help fight blindness worldwide．Inside a DC-8 aircraft, there is a fully-equipped teaching hospital with television studio and classroom．Doctors are taught the latest techniques of bringing sight back to people there．Project ORBIS also aims at promoting peaceful cooperation（合作） among countries．

    ORBIS tries to help developing countries by providing training during three-week medical programs．ORBIS has taught sight-saving techniques to over 35,000 doctors and nurses, who continue to cure tens of thousands of blind people every year．ORBIS has conducted 17 plane programs is China so far．For the seven to ten million blind in China ORBIS is planning to do more for them．At the moment an ORBIS is working on a long-term plan to develop a training center and to provide eye care service to Shanxi Province．ORBIS needs your help to continue their work and free people from blindness．

    For just US$38,you can help one person see; for $380 you can bring sight to 10 people; $1,300 helps teach a doctor new skills; and for $13,000 you can provide a training program for a group of doctors who can make thousands of blind people see again．Your money can open their eyes to the world．Please help ORBIS improve the quality of life for so many people less fortunate than ourselves．

    Sunstroke (中暑) is a condition that can quickly go from dangerous to deadly, especially if proper care isn't given immediately.

    Sunstroke, sometimes called heatstroke, is a result of the body temperature rising above safe limits. This causes the body's necessary functions to stop working.

    It's usually pretty easy to avoid sunstroke, as long as proper action is taken. In that case, you need to act as quickly as possible to return that person's body to a safe temperature. Here are a few tips to help treat sunstroke.

Call for help

    Call to get an ambulance as quickly as possible. This should be the first thing you do, especially if the sunstroke person has fainted(昏倒). Also, call for help from anyone nearby if you're in a public place. If there's no one around, call someone nearby if they can get there sooner than an ambulance. Ask everyone to bring you as much water as possible, if there isn't much nearby.

Get the person to a cooler area

    If there's a building nearby, aim for that. Anywhere with plenty of air conditionings and water is perfect. If a building isn't available, bring the person to a well shaded area.

Get the water flowing

    If the person is still conscious, get him or her to drink water. If there's a bathtub available，fill it with cool water and put the person in it.

If your water supply is limited, you have to save it. Dampen a towel or shirt and put it on the person's body. Focus on the face, neck，and chest.

Fan the person

    Getting moving air over the person cools him or her down. Use anything, a towel or sheet, a shirt your hands，or a piece of board. This is where having many people around really helps, as they can combine to fan the entire body.

    Do you believe in the power of music? If you're like most kids these days, you probably have an electronic device loaded with hundreds or even thousands of your favorite songs. At any moment in time, you can fill your headphones with the sounds of a particular song that suits your mood at that exact time.

    Are you getting ready for a big soccer match or do you need to get excited? Maybe some hip hop with a strong beat will do the trick! Besides, you might be ready to study for a big exam the next day. To calm your nerves and help you concentrate, a little bit of Mozart might make memorization more manageable.

    But is there any scientific evidence of these effects that music seems to have? You bet there is! Scientists have long recognized the power of music. Over the years, many studies have been conducted to examine in greater depth the nature and extent of the effects music has on people.

    For example, scientists at the University of Missouri have found that listening to music can have a positive effect on your mood. Their research gives scientific credibility(可信性)to the behavior that many people have already experienced on their own: listening to upbeat music can brighten your day and boost your mood.

    Other studies have shown that upbeat music isn't the only type of music that can be helpful, however. When people are sad or have suffered a personal loss, sad music can be helpful because people identify with the tone and lyrias(歌词)of the music. Likewise, people under a lot of stress or experiencing upsetting situations can benefit from listening to angry music. Although angry music might not help you if you're in a normal mood, its tone can benefit you when you are dealing with stressful and upsetting situations.

    Artificial intelligence can predict when patients with a heart disorder will die, according to scientists.

    The software learned to analyze blood tests and scans of beating hearts to spot signs that the organ was about to fail. The team, from the UK's Medical Research Council, said the technology could save lives by finding patients that need more aggressive treatment. The results were published in the Journal of Radiology.

    According to the researchers, high blood pressure in the lungs damages part of the heart, and about a third of patients die within five years after being diagnosed. There are treatments: drugs, injections straight into the blood vessels, a lung transplant. But doctors need to have an idea of how long patients might have left, in order to pick the right treatment.

    The software was given scans of 256 patients' hearts, and blood test results. When this data was combined with eight years of patient health records, the artificial intelligence predicted when patients would die.

    The software could look about five years into the future. It correctly predicted those who would still be alive after one year about 80% of the time. The figure for doctors is 60%.

    The team now want to test the software works in other patients in different hospitals before assessing whether it should be made widely available to doctors. The researchers also want to use the technology in other forms of heart failure, such as cardiomyopathy, to see who might need a pacemaker or other forms of treatment.

    Dr Mike Knapton, from the British Heart Foundation, said, "This exciting use of computer software in medical practice will help doctors in the future to make sure that patients are receiving the correct treatment before the condition deteriorates and leaves them needing a lung transplant. The next step is to test this technology in more hospitals with heart disease."