Five hundred years after the Portuguese became the first Europeans to establish sea trade with China, a town in northern Portugal is counting on its youth to secure a new foothold in the Asian giant.

The small industrial town of Sao Joao da Madeira, Portugal's shoe capital which specialises in luxury models, has now made Mandarin compulsory for its 8- and 9-year-olds.

The aim is to give their youth the competitive tool to help sell its footwear to China.

And the government, battling to put six years of debilitating crisis behind, is watching the town's experiment closely to see if it can be replicated throughout the country.

"Chinese is the key which will open the doors to the world's biggest market," said Dilma Nantes, Sao Joao da Madeira's city councillor on education.

China may be known as the factory of the world, and is indeed the biggest producer of footwear -- making 10 billion pairs a year -- but Portuguese shoe-makers are starting to step into the huge Asian market.

Affluent Chinese with a taste for luxury are increasingly fond of handmade Portuguese footwear, which are the world's second most expensive after Italian shoes.

As Portugal battles to encourage growth after a prolonged contraction that saw unemployment soar past 17 percent, the industry is key in helping the country export its way out of the slump.

Exports of footwear by Portuguese brands to China soared from 10,000 pairs in 2011 to 170,000 pairs in 2013, reaching sales of 5.4 million euros ($6.7 million).

If sales of footwear made in Portugal for foreign brands were included as well, 2013 revenues surpass 20 million euros -- although still a fraction of the total shoe exports reaching 1.7 billion euros that year.

- 'Young and learning fast' -

Sao Joao da Madeira, a city of only 20,000 inhabitants, wants to get ahead of that curve by training their children from young to speak Mandarin.

And the children appear to enjoy it.

"I would like to see the Great Wall," nine-year-old Eduardo said.

His classmate Daniela decided: "Chinese is not particularly difficult."

"They are young and learning fast," their Chinese teacher Wang said, smiling.

The idea is for the children -- who started the classes when they were eight -- to carry on with the language studies until the end of secondary school.

In one workshop in the industrial town, the boss of the company, Mario Tavares, is convinced that the move would give the children a clear advantage over their peers in doing business with the Chinese one day.

Tavares's firm Tape began selling to China in 2013, starting with just 200 pairs, but he hopes that figure will soar five times to 1,000 in 2014.

Yet even that is just a drop in the ocean for the company, which exports a total of 160,000 pairs worldwide every year.

"China has the potential to become our main market one day," he said, adding that the young Mandarin speakers would later on be perfect for "sales jobs or managerial posts at factories".