Plans have been drawn up for a two-storey building with four classes, an admin room, hall and patio next to Ysgol yr Hendre Trelew, the pioneering Welsh-language nursery that this March opened its doors to 25 children (of whom 80 per cent are of Welsh descent).
Although about 90 per cent of the nursery's activities are in Welsh, by Year 1 classes will be taught equally in Welsh and Spanish.
"We'll be looking at incorporating the best elements of the Welsh curriculum with the Argentinian one," said Catrin Morris, the project's education co-ordinator.
She was one of the first teachers to travel to Argentina as part of the decade-old Welsh-language project, which is managed by British Council Wales. She stayed on in Trelew after meeting her husband, Milton Junyent, who is partly of Welsh descent. Their two daughters, Ellen, four, and Maite, three, attend the nursery.
The new school building will cost pound;90,000. The original plot cost "Cylch Cymraeg", the members of the local community, about pound;40,000, financed mainly through fundraising activities in Argentina and Wales.
The goodwill of volunteers will continue to play a role in the next phase.
However, Ms Morris is hopeful that the bulk of the funding will come from the regional government, which has been enthusiastic about bolstering cultural ties with Wales in recent years. Running costs and salaries (one nursery teacher and two helpers) are currently paid by a combination of monthly fees (100 pesos, about pound;20, lower than most local private schools) and fundraising events.
Staff costs will remain relatively low as the current handful of five-year-olds start working their way through Y1 and beyond. But the budget will rise dramatically by 2013 when the first generation of children reach Y7.
Recruiting trained teachers will be a challenge. The Wales Argentina Society may fund a local teacher to travel to Wales in JanuaryFebruary (the Patagonian summer) to observe a school in Wales, for the next two years. And the British Council may send teachers from Wales on exchange visits.
Ms Morris said: "Most Welsh-medium schools in Wales have had to fight negativity within their own community. We haven't had that problem here."