A biologist from the National Park Service discovered a rare and unusual mammoth(猛犸) skull(颅骨) buried in a 13,000-year-old rock layer on the Santa Rosa Island, the second largest landmass in the Channel Islands, California. The fossil of the extinct giant animal is leaving many paleontologists(古生物学家) scratching their heads. Despite the fact that it's possibly the best preserved mammoth skull ever found and of high scientific importance, the species of the individual it belonged to can't seem to be identified yet—it's too big to be a pygmy(特别矮小的) mammoth and too small to have come from a Columbian mammoth. Some say it's a new species while others believe the truth lies somewhere in between.

    The first mammoths showed up in North America around two million years ago, but it was only during the last two ice ages that the Columbian species, which could grow to be up to 14 feet tall, made its way to the Channel Islands 100 miles west of Los Angeles. Once the ice melted, many populations became trapped on the island and evolved into pygmy mammoths, an endemic species(地方种) to the Channel Islands which grew only to six feet tall.

    Judging from its size, the newly found mammoth skull doesn't seem to fit any of the two species, Columbian or pygmy. To make things even more confusing, one of its two tusks(象牙) is nearly five feet long and coiled in a manner that resembles those of fully grown mammoths but the left tusk is shorter and sloped, more like a juvenile(青少年).

    This has caused some scientists to say the Santa Rose skull may belong to a transitional species. Whatever's the case, a following examination of the mammoth's teeth should put the matter to rest. The analysis will also tell us how old the mammoth was when it died, so we can tell for sure whether it was an adult or juvenile.

    More interesting than the mammoth's lineage, however, might be its story. The giant mammal lived 13,000 years ago or roughly the same timeline of the “Arlington Man”, a 13,000-year-old human skeleton also found on Santa Rosa. Some 3,000 years later humans were already spread throughout the continent and the Channel Islands' mammoth went extinct. The present finding might help reveal a link between the two.

    The remains also seem to confirm a long-held assumption that there were two mammoth migrations to the Channel Islands. “The discovery of this mammoth skull increases the probability that there were at least two migrations of Columbian mammoths to the island: during the most recent ice age 10,000 to 30,000 years ago, as well as the previous ice age that occurred about 150,000 years ago,” said USGS geologist Dan Muhs.

Five years ago, when I taught art at a school in Seattle, I used Tinkertoys as a test at the beginning of a term to find out something about my students. I put a small set of Tinkertoys in front of each student, and said:"Make something out of the Tinkertoys. You have 45 minutes today and 45minutes each day for the rest of the week." A few students hesitated to start. They waited to see the rest of the class would do. Several others checked the instructions and made something according to one of the model plans provided. Another group built something out of their own imaginations.

    Once I had a boy who worked experimentally with Tinkertoys in his free time. His constructions filled a shelf in the art classroom and a good part of his bedroom at home. I was delighted at the presence of such a student. Here was an exceptionally creative mind at work. His presence meant that I had an unexpected teaching assistant in class whose creativity would infect(感染) other students.

Encouraging this kind of thinking has a downside. I ran the risk of losing those students who had a different style of thinking. Without fail one would declare, "But I'm just not creative."

"Do you dream at night when you're asleep?"

"Oh, sure."

"So tell me one of your most interesting dreams." The student would tell something wildly imaginative. Flying in the sky or in a time machine or growing three heads. "That's pretty creative. Who does that for you?"

"Nobody. I do it."

"Really-at night, when you're asleep?"

"Sure."

"Try doing it in the daytime, in class, okay?"

    Many of today's parents fondly remember childhood days spent playing outdoors. When children make mud pies and observe ants, it may seem like just fun and games, but the truth is the outdoor play is an important part of growing up healthily. The National Association for the Education of Young Children reports that outdoor play reduces (make…less) stress and restlessness in children and improves their attention.

    Outdoor play is the perfect way to fight against the childhood's obesity(being fat).Research shows that children who play outdoors are more fit and thin, according to the National Center for Physical Development and Outdoor Play. Children who spend time outside on a regular basis  also have healthier immune (免疫) systems. And playing outdoors is a good way to get enough vitamin D.

    Playing outside enables children to relax , reduces tension（紧张）and helps them solve problems. When children play outdoors, they learn to share and cooperate (work together) with one another. Kids who feel confident outdoors are likely to become able clever adults.

    The outdoors is a giant laboratory for learning that improves creative thinking and problem solving. Researchers have found that children learn best when their body, mind and spirit are involved (牵连的), and this appears in outdoor play. Outside activities develop all five senses, which create a powerful learning environment. The outdoors also lets children have the chance to explore (探究), experiment, form questions and create their own ideas about how the world works.

    Although there are the many advantages of outdoor play, time spent outside has been reduced for many of today's children. Kids today spend much more time in front of electronic media than children a generation (代) ago. The lack of outdoor play is tied to the childhood widespread obesity. And experts predict that the situation is so serious that this generation will have much trouble when they grow up. To get kids involved with the outdoors, encourage them to collect rocks, fly kites, climb trees, garden, camp, swim, go fishing, watch birds and butterflies or play games with other children.

    People are always looking for lost cities and occasionally one is found: Borobudur in Indonesia, for example. But perhaps some of the places people look for never existed — or did they? Here are just a few famous mythical (传说中的) cities.

    El Dorado

    El Dorado is a story that began in 1537, when Spanish explorers found the Muisca people in the mountains of what is now Colombia. They heard the story of a man who covered himself with gold and dived into a lake. Then people began to talk of El Dorado — 'the golden man'. Soon people started to think of El Dorado as a place, too — a city of gold and amazing riches. Nowadays, the name 'El Dorado' is still used to mean 'a place where you can get rich quickly'.

    Atlantis

    There was once an island in the middle of the Atlantic Ocean. It was the mythical island of Atlantis. The people of the island were very rich, thanks to the natural resources (资源) on their island. For hundreds of years, they lived simple lives. But slowly they began to change. They started to want power. So the gods decided to destroy Atlantis. Suddenly, the island and its people were swallowed (淹没) by the sea and were never seen again.

    Shambhala

    In Tibetan Buddhist tradition, Shambhala is a mystical (神秘的) country that is hidden somewhere behind the Himalayas. Shambhala is a word from an old language that means 'place of peace' or 'place of happiness'. It is said that there is no war in Shambhala, and in the future, when the world is full of war, a huge army will come out of Shambhala, destroy the world's bad rulers, and start a new Golden Age. Some people say this will happen in 2424.

    Hip-hop culture covers many fields; it includes spoken words, break-dancing, beat-making, painting, fashion, lively design, technology, and more. Hip-hop is becoming the unofficial music in the education world, as more artists launch school programs, summer camps, and other activities connected city youth in the classroom through the beliefs of hip-hop culture. Even more and more university teachers — who once would have been strongly against hip-hop — have joined the crew. In the past two decades, hip-hop culture, including hip-hop education, has become a legitimate(合法的) field of study in universities and the subject of numerous books.

    Hip-hop culture has influenced every piece of American and global culture because the culture is so prevalent. Teachers must be willing to engage in it if it's part of the unique reality of their students' lives. That way, teachers can truly be effective, reaching students in a meaningful, culturally connected way.

    Teachers might at first feel frightened by hip-hop culture, an area in which they might not have previous knowledge or experience. But a lack of knowledge is actually a blessing; the best trained hip-hop educators have been those that are at the beginning disconnected(分离的) from the culture. One of the biggest sayings in hip-hop is “keep it real”. If a teacher comes to the classroom and says, “I don't know hip-hop, but I recognize that it's your culture and I want to learn,” the kids will teach the teacher, and then the students will be more willing to learn from that educator. Hip-hop is about a respect for youth culture.

    "An apple a day keeps the doctor away" is one of the most common sayings in the English languages. This is because apples were one of the first foods that medical professionals recognized as healthy­their benefits became obvious when  quite simply, doctors found that people who ate apples were sick less often than those who did not. Today we have a more specific understanding of why apples are so beneficial to overall health.

    Apples can help keep your levels of bad cholesterol (胆固醇) down. The pectin (果胶) in apples helps you to maintain cardiovascular health and reduce LDL cholesterol(which is the "bad" kind). Apples themselves do not add cholesterol to your diet and are full of water and fiber to help prevent the cholesterol in other foods you might digest. According to Health Diaries, people who eat two apples per day may lower their cholesterol by as much as 16 percent.

    Apples are naturally low in calories and high in water content. Eating an apple can satisfy your hunger and keep you from reaching for high-sugar, high-calories snacks. By eating apples, you will be more able to maintain a healthy weight because they fill you up, potentially stopping you from eating food that encourages a waistline increase.

    Apples contain respectable levels of boron (硼) which helps build healthy bones, and can also prevent diseases like arthritis. Apples are rich in vitamin C, which is known to help build immunity.

    Studies have shown that apples can decrease the risk of breast cancer, colon cancer, and liver cancer. One theory is that the apple skins are responsible for this, so be sure not to peel your apple before you eat them, as you could remove some of the health benefits.