When ysgol yr Hendre opened its doors to 25 pupils in Argentina it fulfilled its ambition to be the only Welsh-language primary school outside the UK.
But it hardly imagined that, within four years, it would outgrow its central location in the town of Trelew, named in honour of Lewis Jones, one of the founders of the Welsh colony in Patagonia, Argentina.
When pupil numbers doubled in just three years, the school realised that once the first intake of nursery children reached Year 7, in 2013, it would have to find space for 170 students - 100 more than predicted.
It is now set to build a new school to house an unexpected demand for Welsh-language education in the South American country.
"The background of the children has changed a lot in the last four years," said Catrin Morris, a parent and teacher. "In the beginning, 80 per cent or more of the kids attending had some kind of Welsh background. Now half the school's intake are Argentines of non-Welsh descent. For instance, we have one family from Uruguay who are learning three languages - Spanish and Portuguese at home and now Welsh. We didn't think it would be so popular."
The site of the new school is only a stone's throw from Moriah chapel, where the remains of many of the first Welsh settlers, who arrived in the area in 1865, are buried.
"The education Ysgol is offering is very innovative in Argentina," Ms Morris says. "There are lots of bilingual schools, but none offer core subjects such as maths in a non-Spanish language. We try and teach maths in Welsh, even if it means giving extra maths classes in Spanish also. We try to split everything."
The school cannot rely solely on regional government support, and a fundraising effort will take place in August when Welsh tenor Rhys Meirion plans a tour of Welsh Patagonia to raise money for the school.
A former headteacher himself, Mr Meirion admires the "old-fashioned individual attention in small class sizes" at Ysgol yr Hendre, something which accounts for its growing waiting list of pupils from Welsh and non- Welsh backgrounds.
The school even sticks to the daily ritual of singing the national anthem while raising the Argentine flag. "We do this . but in Welsh," Ms Morris said.