It is easier to float in the ocean than it is to float in a swimming pool.Do you know why?

    Ocean water is full of salt--and salt water can hold up more weight than fresh water.See for yourself!

You will Need:

3 cups of warm water

Measuring cup(量杯)

Wide-mouthed jar

Salt

Spoon

Raw(生的)potato

You Will Do:

⒈Pour 1.5cups of warm water into the jar.

⒉Add 1/3 cup of salt.

⒊Stir(搅拌) until the salt is completely dissolved.

⒋Add another 1.5 cups of water.Pour it slowly over the back of the spoon into the jar so that the two liquids will not mix together.

⒌Gently place the potato into the jar.Do not drop it.

    What Will Happen:

    The potato will sink--but only halfway!

    Why?

    Salt water is heavier than fresh water,so it will stay on the bottom.The fresh water will remain on top.

    The potato is heavier than the fresh water,but it is lighter than the salt water.That is why the potato will sink halfway down.

    When my son, Bob, was in the third grade, he saved all his pocket money for over three months to buy Christmas presents. The third Saturday in December, Bob said he had made his list and had twenty dollars in his pocket.

    I drove him to a nearby supermarket. Bob picked up a basket and went in while I waited and watched in the car. It took Bob over 45 minutes to choose his presents. Finally he came to the checkout counter and reached into his pocket for his money. It was not there! There was a hole in his pocket, but no money. Bob stood there holding his basket, tears falling down his face.

    Then a surprising thing happened. A woman came up to Bob and took him in her arms. "You would help me a lot if you let me pay for you," said the woman. "It would be the most wonderful gift you could give me. I only ask that one day you will pass it on. When you grow up, I would like you to find someone you can help. When you help others, I know you will feel as good about it as I do now."

    Bob took the money, dried his tears and ran back to the checkout counter as fast as he could. That year we all enjoyed our gifts almost as much as Bob enjoyed giving them to us.

    I would like to say "thank you" to that very kind woman, and tell her that four years later, Bob went from house to house collecting blankets and clothes for the homeless people in the fire. And I want to promise her that Bob will never forget to keep passing it on.

    There are many reasons why I encourage people to travel, and I know that the experience will make one a better person.

    I remember when I was travelling I began to know the world better. The world is not just about me, my small town and home. Although you will meet different people from all over the world, you will realize that people are similar in their dreams, hopes and feelings. Enjoy exploring the different cultures, and you will also find that people are different in some of the things they do and how they live. Once you understand their ways, it need not be strange or scary. Often we read stories about other cultures in books. Only when we visit their areas do we find that those stories are something wrong.

    One thing you may find out is that there are problems all over the world. We can't just get money to send to these areas and hope that will work them out. The world should get involved（干预）and help wherever there are problems. People everywhere should be given a chance. It is so easy to ignore this if one does not travel and explore. One can look around and see that so many people have many challenges worse than ours. One can realize that sometimes our biggest problems are not that big after all.

    On your journey you will meet lots of new friends. Talking to strangers and finding about their lives is a great way to spend your time. you will certainly be more confident after having to cope with problems and make many decisions along the way.

    When you travel, you have to be on your own in some situations. You will surprise yourself by how well you can do that. All your special experiences could make an interesting book to read. It would be filled with all your adventures and special memories.

    Traveling around and seeing so much happening in the world around us is a wonderful experience. If we could all just travel a little more and share our experiences, we would all be better people and the world would be a better place.

    Schools across the world are trying to come up with solutions to keep students active. Some are replacing traditional classroom chairs with exercise balls or standing desks. At Ward Elementary School in Winston, North Carolina students have adopted a new program that requires riding fixed bikes while reading.

    'Read and Ride5 is the creation of school counselor Scott Ertl, who came up with the idea while he was exercising and reading at the gym. Believing it would be a fun way to convince students to become more active, he placed one in the comer of his classroom and encouraged them to use it during independent reading classes.

    It was so popular that Ertl decided to add more bikes and offer the Read and Ride program to the entire school. Today Ward Elementary has a dedicated exercise room filled with bikes that can be used by students while completing their daily reading assignments.

    Besides making reading more fun, the program also helps students exercise at a comfortable pace without the pressure that comes with regular sports-related activities. It is also a perfect way to release energy during days when the weather is not helpful to outdoor activities.

    Most importantly, however, are the program's academic benefits. A year after Read and Ride was introduced at Ward Elementary School, students actively involved in the program demonstrated an astonishing 83% reading proficiency. Those that had not taken advantage of the exercise bikes tested at a much lower, 41%.

    Though the substantial improvement in academic achievement cannot all be attributed to programs like Read and Ride, experts believe they are a significant contributor. That's because studies have shown that physical activity stimulates (刺激) brain cells and helps prepare it for learning. As word of the difference made by this easy to execute exercise program spreads, don't be surprised to find schools across the country adopt “Read and Ride” for their students.

    As any plane passenger will confirm, a crying baby is almost impossible to ignore, no matter how hard you try. Now scientists believe they may have worked out why. A baby's cry pulls at the heartstrings(扣人心弦)in a way while other cries don't, researchers found.

    Researchers found that a baby's cry can trigger unique emotional responses in the brain, making it impossible for us to ignore them—whether we are parents or not. Other types of cries, including calls of animals in great pain, fail to get the same response…suggesting the brain is programmed to respond specifically to a baby's cry.

A team of Oxford University scientists scanned the brains of 28 men and women as they listened to a variety of calls and cries. After 100 milliseconds — roughly the time it takes to blink (眨眼) —two parts of the brain that respond to emotion lit up. Their response to a baby's cry was particularly strong. The response was seen in both men and women—even if they had no children.

    Researcher Dr Christine Parsons said, "You might read that men should just notice a baby and step over it and not see it, but it's not true. There is a special processing in men and women, which makes sense from an evolutionary(演化的)view that both men and women would be responding to these cries." The study was in people who were not parents, yet they are all responding at 100ms to these particular cries, so this might be a fundamental response present in all of us regardless of parental status.

    Fellow researcher Katie Young said it may take a bit longer for someone to recognize their own child's cries because they need to do more "fine-grained analysis". The team had previously found that our reactions speed up when we hear a baby crying. Adults performed better on computer games when they heard the sound of a baby crying than after they heard recordings of adults crying.

    When first entered, Vanak Restaurant does not look like much of a restaurant, but once the pleasant smells of kabob (烤肉串) hit the senses, you are incapable of calling it anything less.

    Owned by a local couple, this Persian restaurant has an inviting, homelike atmosphere that many restaurants lack.

    The space is small with only a few dining tables and nearly no decoration, but the environment is truly charming.

    Lying in a hardly noticeable street corner, the restaurant still attracts all customers, especially those experienced in the delights of Middle Eastern cooking.

    A common sight is that of old Persian men sitting in the corner talking loudly about world topics, watching news events on TV, drinking a black tea known as Persian chai, and reading local Persian newspapers all the while trying to finish off their plates piled with food.

    The variety of food at the restaurant is limited, but the amount of each dish is fairly large. Most of the meals can serve two people and are under $10, so not only is it affordable but practical as well.

    The food especially appeals to health-conscious eaters because each dish is very healthy, made with limited fat and oil and served straight off the grill (烤肉架).

    The main dish that the restaurant is popular for is its kabobs, which are different styles of grilled meat.

    One delicious and extremely healthy dish is the Joojeh Kabob, which is made of grilled chicken pieces served with either rice or bread. Another great kabob is the Chelo Kabob, a kabob consisting of grilled beef.

    Although the restaurant is small, the atmosphere and the food is delicious. It is a place that should not be overlooked.