SHANGHAI, June 1 (Xinhua) -- Shuttling between pavilions at the Shanghai World Expo, 14-year-old Wu Xinhui feels he has traveled to many countries in one day.

"I like the roller coaster in the Switzerland Pavilion most and playing basketball by touching a screen in Lithuania," says the Shanghai Fengjing Art Middle School first grader.

He was impressed by new technology on display, including a polluted water treatment system in the China Pavilion, solar power generation and wind power generation. "These technologies can help cut carbon emissions, which is important as the earth has limited resources.

"My dream city would have more exciting architecture and people would take care of the environment," Wu said.

The World Expo provided a variety of activities especially for International Children's Day, but Wu had his suggestions. "Some pavilions just show films on their ethnic culture.... We like real, genuine things, more interactive things. The queues are too long and more doors should be open to let visitors in."

The Russian Pavilion had miniature constructions built from children's paintings of their dream cities: tree-house cities, a school-city on tortoise back and candy-shaped cities.

"In my future, people have decided to live on trees because there is too little space left on the ground so we will live in tree-houses. In the meantime, the plants and animals will recover on the ground," said a Russian teenager in a videotaped message on his tree-shaped city.

Alina Radchenko, head of administration of the Civic Chamber of the Russian Federation, said the displays came from a national competition among children in Russia to create the city of their future.

"They essentially did all the planning and the plans were produced by the adults. This is a unique example how children can take part in shaping their future," she said.

"Child must be treated as a first priority in city planning though not as a full decision maker. So instead of having adults decide what is most proper for city planning, involve the children in the process, think about their interests, try to take their interests into consideration," she said.

In the Denmark Pavilion, the Little Mermaid, Denmark's iconic statue based on the story by Hans Christian Andersen, attracted children waiting to take photos with the fairytale beauty.

Christopher Bo Bramsen, Commissioner General of Denmark, said he believed the 96-year-old statue contributed greatly to the glamour of the pavilion.

He said Chinese children knew more about Andersen than people in other parts of the world.

"A good city should be one where children live happily. Two concepts are most important to define a good city: welfare and fairytales. People, especially children, should live in a city with clean water, air and good traffic, along with some cultural aspects, including theaters, paintings and beautiful monuments," he said.

Six-year-old Yu Haoming was playing an armed policeman in a children's vocational role-playing community.

"It's cool to be a policeman. My job is to catch bad guys," said the boy. With four other children, he entered a bank, staffed by other role-playing children, to investigate a suspected robbery.

His mother, Yu Cuili, said, "I don't want to stuff him with too much knowledge. I hope my son can grow naturally and be happy."

Anatoly Prokhorov, art director of Smeshariki, a popular animated cartoon series in Russia, said, "It's like integrating the disabled into our society decades ago. Now the disabled are equal with others in our society. And now we should do the same with children.