Bill Gates recently predicted that online learning will make place-based colleges less significant, and five years from now, students will be able to find the best lectures in the world online. I applaud Mr. Gates. But what's taking us so long?

    As early as 1997, MIT(麻省理工) decided to post videos of all university lectures online. for free, for all people. But today, how many students have you met who mastered advanced mathematics or nuclear physics from an MIT online video? Unfortunately, the answer is not many. The problem is the poor quality of online education websites and the experience they provide to students. Those who go to the MIT website and watch courses online are surely very smart people, but it's not like playing a video game such as World of Warcraft. Only the most ardent students, those who are highly motivated, will devote themselves to studying these boring online videos.

    The real question is why we aren't spending more to develop better online education platforms. Where is the Avatar of education? Think about this. The market for Hollywood films per year is worth around 30 billion USD. Education in the world is a trillion-dollar-a-year market, hundreds of times bigger than Hollywood movies. Yet the most expensive digital learning system ever built cost well under 100 million dollars.

    Bill Gates' prediction is going to happen. There is no doubt about it. But it will only happen when we create high level educational content and experiences that engage and excite more than has ever been possible in the real world.

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    In 1880, fourteen-year-old Matthew Henson loved to hear sailors tell tales of their exciting lives at sea. The travel, the adventure, the danger, and the steady pay were all attracting young Henson. One day, he found a job as a cabin boy on a beautiful ship called the Katie Hinds. For the next five years, Henson sailed around the world. With the help of the ship's captain and other members of the crew, Henson learned mathematics, navigation, history, geography, and many other subjects. By the time he left the Katie Hinds in 1885, Henson was well educated and had become an excellent seaman.

    Unable to find work anywhere else, Henson took a job in a hat shop in Washington, D.C. One day in 1887, a man came in to buy a hat. The man, Robert Peary, asked the owner if he knew anyone with experience at sea. Peary would soon travel to South America for the U.S. government. He needed experienced men to accompany him. The shop owner knew about his young employee's skills and experience on ocean journeys, so he introduced Peary to Henson.

    Using his map-reading and sailing skills, Henson proved himself to be a worthy and smart seaman. Peary soon made Henson his assistant（助理）, and they became close friends. One day Peary told Henson about his real dream: to be the first man to stand on “the top of the world” at the North Pole. He asked Henson to help him make his dream come true. Over the next five years, the two explorers made two trips together to the Arctic. However, they were not able to reach the pole either time. The cold, wind, and ice were worse than either of them had ever imagined.

    In 1908, Peary and Henson were ready to make their final attempt at reaching the North Pole. Both men were over forty years old. The years of hardship in the arctic cold had made them suffer a lot. This would be their last chance. With four Inuit（因纽特）guides, they made a mad rush straight across the ice toward the pole. Peary's feet were injured and he had to be pulled on a dogsled. In April 1909, Henson's instruments showed they were standing at the North Pole. Together Henson and Peary planted the American flag in the snow.

    In later years, Robert Peary and Henson were greatly honored for their achievements. Today, the two friends and fellow explorers lie in heroes' graves not far apart in the Arlington National Cemetery.

    Half an hour into a cooking competition at Green Street Academy, Tyana Givens, 15, dipped a plastic spoon into a pot with tomatoes, bell peppers, onions, garlic and mushrooms over a burner in a science classroom. She and the two other students, Kalimah Ball and Maya Smith, were making meat sauce.

    The girls had spent the past five weeks learning how to grow their own produce using food computers-tabletop greenhouses controlled by computer programs-at Green Street Academy, a charter school in Baltimore. The course, which weaved together lessons on programming, food systems and agriculture, ended with an “Iron Chef”-style cooking contest.

    With the help of instructor Melanie Shimano, the girls finished their contest successfully using the food they planted in tabletop greenhouses. The tabletop greenhouses can control temperature, light and water inside using the computer code that the students wrote by themselves. Shimano, a 26-year-old entrepreneur, piloted(试行)the course as part of Green Street Academy's junior biotechnology class in the spring and will expand the program to other schools in the fall.

    “Technology is not something that a lot of teachers have a lot of resources for all the time, but it's something that's not difficult to do with a relatively low amount of funding,” Shimano said. “Baltimore is a center for startups and food, so kind of fostering that culture of being into technology and into design and seeing all the pieces fit together is really cool.”

    While her course is unique to Baltimore, it's part of a broader program born at the Massachusetts Institute of Technology's Media Lab called the Open Agriculture Initiative, or OpenAg, which aims to create inventive, sustainable food systems through open-source technology. In addition to 10 full-time staff and researchers, OpenAg is primarily an online community of about 1,400 educators, growers, chefs and retailers in 47 countries, according to Hildreth England, OpenAg's assistant director.

    “The interest level across the board generally comes from folks who are concerned about food systems and concerned about the environment, and it's usually a combination of the two,” England said.

    Every man wants his son to be somewhat of a clone（克隆）, not in features but in footsteps. As he grows you also age, and your ambitions become more unachievable. You begin to realize that your boy, in your footsteps, could probably achieve what you hoped for. But footsteps can be muddied and they can go off in different directions.

    My son Jody has hated school since day one in kindergarten. Science projects waited until the last moment. Book reports weren't written until the final threat.

    I've been a newspaperman all my adult life. My daughter is a university graduate working toward her master's degree in English. But Jody? When he entered the tenth grade he became a "vo-tech" student (技校学生). They're called "motorheads" by the rest of the student body.

    When a secretary in my office first called him "motorhead", I was shocked. "Hey, he's a good kid," I wanted to say. "And smart, really."

    I learned later that motorheads are, indeed, different. They usually have dirty hands and wear dirty work clothes. And they don't often make school honor rolls (光荣榜).

    But being the parent of a motorhead is itself an experience in education. We who labor in clean shirts in offices don't have the abilities that motorheads have. I began to learn this when I had my car crashed. The cost to repair it was estimated at $800. "Hey, I can fix it," said Jody. I doubted it, but let him go ahead, for I had nothing to lose.

    My son, with other motorheads, fixed the car. They got parts (零件）from a junkyard, and ability from vo-tech classes. The cost was $25 instead of $800.

    Since that first repair job, a broken air-conditioner, a non-functioning washer and a non-toasting toaster have been fixed. Neighbors and co-workers trust their car repairs to him.

    These kids are happiest when doing repairs. They joke and laugh and are living in their own relaxed world. And their minds are bright despite their dirty hands and clothes.

    I have learned a lot from my motorhead: publishers need printers, engineers need mechanics, and architects need builders. Most important, I have learned that fathers don't need clones in footsteps or anywhere else.

    My son may never make the school honor roll. But he made mine.

    What will people die of 100 years from now? If you think that is a simple question, you have not been paying attention to the revolution that is taking place in bio-technology(生物技术). With the help of new medicine, the human body will last a very long time. Death will come mainly from accidents, murder and war. Today's leading killers, such as heart disease, cancer, and aging itself, will become distant memories.

    In discussion of technological(技术的) changes, the Internet gets most of the attention these days. But the change in medicine can be the real technological event of our times. How long can humans live? Human brains were known to decide the final death. Cells are the basic units of all living things, and until recently, scientists were sure that the life of cells could not go much beyond 120 years because the basic materials of cells, such as those of brain cells, would not last forever. But the upper limits will be broken by new medicine. Sometime between 2050 and 2100, medicine will have advanced to the point at which every 10 years or so, people will be able to take medicine to repair their organs（器官）. The medicine, made up of the basic building materials of life, will build new brain cells, heart cells, and so on—in much the same way our bodies make new skin cells to take the place of old ones.

    It is exciting to imagine that the advance in technology may be changing the most basic condition of human existence, but many technical problems still must be cleared up on the way to this wonderful future.

    Race walking shares many fitness benefits with running, research shows, while most likely contributing to fewer injuries. It does, however, have its own problem.

    Race walkers are conditioned athletes. The longest track and field event at the Summer Olympics is the 50-kilometer race walk, which is about five miles longer than the marathon. But the sport's rules require that a race walker's knees stay straight through most of the leg swing and one foot remain in contact (接触) with the ground at all times. It's this strange form that makes race walking such an attractive activity, however, says Jaclyn Norberg, an assistant professor of exercise science at Salem State University in Salem, Mass.

    Like running, race walking is physically demanding, she says, According to most calculations, race walkers moving at a pace of six miles per hour would burn about 800 calories(卡路里) per hour, which is approximately twice as many as they would burn walking, although fewer than running, which would probably burn about 1,000 or more calories per hour.

    However, race walking does not pound the body as much as running does, Dr. Norberg says. According to her research, runners hit the ground with as much as four times their body weight per step, while race walkers, who do not leave the ground, create only about 1.4 times their body weight with each step.

    As a result, she says, some of the injuries associated with running, such as runner's knee, are uncommon among race walkers. But the sport's strange form does place considerable stress on the ankles and hips, so people with a history of such injuries might want to be cautious in adopting the sport. In fact, anyone wishing to try race walking should probably first consult a coach or experienced racer to learn proper technique, she says. It takes some practice.