A 13-year-old pupil made history last month when she delivered a presentation in Welsh in the European Parliament.
Shazia Marquis, from Cathays High School in Cardiff, outlined a new youth charter to ministers. It was the first time a Welsh-language speech was simultaneously translated to ministers.
Together with young people from 10 European countries, Shazia, who has been learning Welsh since primary school, helped to compile the Youth Charter on Inclusion and Diversity in Education.
The document outlines the importance of tolerance and cultural diversity in Europe's schools. It also says that school councils should play an important role in education.
Rod Phillips, head of Cathays High, travelled with the pupils to Brussels.
"I was very impressed with the way in which this group of young people, from 10 different countries, worked together so effectively to negotiate this inspiring charter," he said. "I was particularly proud of Shazia."
Shazia said: "It's not just our school - it's a whole European thing, and I thought it would be quite a different experience for me. It was good because I could represent Wales and use the language. I was a bit nervous, but I was proud to represent Wales."
Shazia is also conversant with French and Gujerati.
The project will continue for two years and pupils will work with schools in the Netherlands and Germany, as well as Wales, to develop and promote the charter to young people and teachers throughout Europe.
"We should all have the opportunity to learn about different cultures and languages," said Shazia. "I think if people realise why others do what they do, they'll be less prejudiced."
Also representing Cardiff in Brussels was Gareth Jones from Willows High, Jamila Boukes from Fitzalan High and Katie Pritchard from Cardiff High.