What do you do when you have a problem? Would you ask a crowd of strangers for a solution? It may sound strange, but it has inspired innovation and is the thinking behind “challenge prizes”.

Challenge prizes come in many shapes but the basic concept remains the same. Rather than consult an expert for a solution, you offer the prize to anyone who believes they can solve it and present the first to do so with a prize. Many would argue. “Who is better qualified than an expert?” But actually, not using experts seems to result in a great deal of thinking outside of the box.

Some argue that formal education can kill creativity as it sometimes only teaches a single method to achieve a task. In the same way, some suggest that experts can have the same problem. “If we set up a challenge prize, the ‘experts’ that compete in it may tell us it can’t be done.” says Marcus Shingles, former CEO of the XPRIZE Foundation.

There are other advantages too. “You’re not asking people to use a particular solution to solve that problem. So you get this large amount of diversity,” adds Shingles.

Yet, challenge prizes also come with problems. You don’t want to create a challenge prize which encourages people to solve a problem where there is no demand. In 1979, a prize of £ 100,000 was claimed by the first person to fly under human power across the English Channel. Yet, it has not led to the adoption of human-powered flight as a form of travel. And there are those who devote their time and energy only to see no return at all. Overall, challenge prizes don’t seem to be going out of style anytime soon. To many, the challenge to innovate and the attraction of the prize are too much to resist.

Sometimes we only appreciate something when we realize we may lose it. That is the story of the Everglades. A shallow slow-moving river, the Everglades once covered about 18,000 square miles of southern Florida. Until the 1900s, few people lived in the grassy wetlands. Not much was understood about the unique balance of nature that existed there. Plants, creatures, and water had formed a remarkable ecosystem.

By the early 1900s, Florida’s pleasant winters attracted more people. Visitors became new permanent residents. They built homes and roads. The conditions looked good for farming, so the newcomers planted large agricultural crops. But South Florida’s cycle of flooding was a problem. To address that, developers attempted to drain (排水) the land. They also built structures to control water levels and flow.

Those changes made it easier for more people to live year-round in South Florida. However, they also disturbed life in the Everglades, which depends on freshwater regularly refilling the land. The area’s growing human population needed freshwater. And large farms consumed large quantities of freshwater. By the mid-1900s, water levels in southern Florida began to go down. Lack of freshwater wasn’t the only problem. As more and more land was developed for people and farms, the Everglades’ historic boundaries contracted. Loss of habitat and hunting threatened the survival of native species in the Everglades.

Some people hoped that the government’s recognition might save the Everglades. They fought for it. Everglades National Park was established in 1947. It became the first park in the United States created for its biodiversity.

Now, Everglades National Park protects 1.5 million acres along the southern tip of Florida. An amazing variety of creatures live there. About 360 different species of birds have been sighted in the park. Nearly 300 different species of fish have been identified. About 40 species of mammals and 50 species of reptiles inhabit the park. Nature still rules in the Everglades, a place worth understanding, appreciating, and protecting.

If you watch British television on March 15, you might be surprised to see celebrities (名人) wearing funny red noses and joking around. But don’t worry. They’re not mad. It's all part of a money raising event called Red Nose Day.

Founded in 1985 by two British comedians, the aim of the event is to raise money to fight poverty and injustice in the UK and Africa. Celebrities and public figures support the event by making appearances on comic TV shows. For example, the former UK Prime Minister David Cameron once appeared in a music video by One Direction, which the band produced for the event.

Britons don’t just raise money for charitable causes on one day a year, but they do it all year round. One way of doing so is by shopping in charity shops. These small shops sell clothes, books and household goods just like any other shop except that they’re all second-hand.

There are nearly 10,000 charity shops in the UK. Their business model is simple: anybody who has things they don’t want anymore can donate them to a charity shop, where they are checked for damage, cleaned and priced. The money that is made by selling them is used for a charitable cause.

The idea of buying used clothes may sound unpleasant, but for shoppers who have less spending money, it has been a welcome option. Now, shopping at charity shops is also becoming popular with young people looking for alternative fashion. “You can find very unique clothes for a very cheap price. It doesn’t bother me that other people may have worn them. I simply wash them before I wear them.’’ said Anne Marie, a 19 year old from the US.

So next time you spot a charity shop, why not go inside? Who knows, you might find a lovely dress for just a few pounds. Even better, you can enjoy wearing it in the knowledge that your money helped a good cause.