3 . Rosie the Riveter was a World War II nickname for women who worked in factories and shipyards all across the country. The two women talked about here were not like Rosie. They, and four others, were working on a machine at the University of Pennsylvania, called ENIAC (Electronic Numerical Integrator and Computer). It was designed to do difficult calculations related to ballistics (弹道), but the war ended before ENIAC was put into use.

Work on it continued, though. The room-sized computer was completely electronic, so it should have been far faster than the other big war-time calculator, the Mark I, developed by IBM. The Mark I, driven by electricity, had moving parts that slowed it down but its instructions could be stored on a paper tape, which gave it a big advantage. In ENIAC, however, every calculation involved putting cables (电缆) into a board.

To program ENIAC, the women had to first analyze hundreds of equations (公式) involved in a particular calculation. Then, they determined which cables should go where, so the machine would do the right steps in the right order. They understood both mathematics and the machine.

Programming was in its early stage in the 1940s; in fact, the term, “to program95 came from the ENIAC team. Women held many of these early jobs. The six ENIAC programmers had been selected from a group of women with degrees in mathematics who worked on other big war-time calculators. Today, computer jobs are controlled by men. Women hold only a quarter of the tech jobs in the United States, though they account for half the workforce. Only 18 percent of computer science graduates today are women. Often the explanation is that girls don't like math, or don't do well in it, but the experience of these earlier women proves otherwise.

4 . Every March, the country celebrates the achievements of women in American history. Even though these achievements go back a long way, most schools didn’t start focusing on women pioneers and their achievements until recently. Today, most schools teach kids about the many contributions women have made to our country.   How did this change come about?

On March 19, 1911, a German woman named Clara Zetkin organized the very first International Women’s Day. Inspired by American working women, the event took on the causes of peace in an effort to end World War I as well as women’s rights. However, people’s interest in International Women’s Day still dwindled over the years. It gained momentum (势头) again in the 1960’s when the women’s movement caused women to wonder why they weren’t included in the history books.

By the 1970s, more female historians began to look back at women’s contributions in history. In 1978, a California school district started Women’s History Week to promote the teaching of women’s history. School officials picked the week of March 8 to include International Women’s Day. It was so popular that, in 1981, Congress passed a resolution, making the week a celebration for the entire country. The concept of studying women’s history continued to grow in popularity. In 1987, a group of women asked Congress to expand the celebration. That same year, Congress declared the entire month of March National Women’s History Month.

Today, schools and communities across the country celebrate the month with special lessons and activities designed to teach the ways women have helped shape the US. The women who have worked hard to make Women’s History Month a reality would like to see women’s history studied all year, not just every March. In 1996, the National Women’s History Museum was founded. It is a non-profit organization dedicated to preserving and celebrating the various historic contributions of women. The organization is working with Congress to open a permanent (永久的) museum site in Washington, D.C.

5 . The first Ferris wheel was built for the 1893 World's Columbian Exposition in Chicago. The people who planned the fair were looking for an attraction that would bring people to Chicago. The Eiffel Tower had been a great success for the fair in Pairs in 1889, and they wanted something like that.

George Ferris handed in drawings of a giant wheel that people could ride on. At first everyone laughed at his strange idea. But Mr. Ferris didn’t give up, and finally the idea was accepted. The ride opened in June of 1893.

That first wheel had thirty six enclosed cars, each holding sixty passengers. When filled it carried 2,160 people. During that summer in Chicago one and a half million people rode the Ferris wheel, which was named after Ferris. Six platforms were used to pick up and drop off passengers. Each ride was two full turns of the wheel. On the first turn, it made six stops for loading. Then the second turn was a nonstop nine-minute ride. Each car had five large glass windows in front and in back, giving everyone a great view of Chicago and Lake Michigan.

After the fair the ride was moved to a nearby amusement park built especially to show off the wheel. In 1904 it was moved again—this time to St. Louis for the Louisiana Purchase Exposition. After the fair in St. Louis closed, the wheel stood unused. In 1906 it was finally sold to a company for scrap(废弃材料）metal. It took 200 pounds of dynamite to bring it down.

Fortunately a Chicago bridge builder, W. E. Sullivan, figured out how to make a smaller Ferris wheel that could easily be taken apart and put together. In 1906 he started the company that still makes many of the Ferris wheels used today.

But whenever you ride one remember that it all began with George Ferris’ very strange idea.