People opposed to plans for a new Welsh-medium primary school in Powys have handed in a petition at the Welsh assembly.
The school at Brynderi in Ystradgynlais could replace Ysgol Ynyscedwyn and Ysgol Cwmtwrch, but an action group claims the site is too small.
About 100 people demonstrated as the petition was handed over.
Powys council has said it is the most expensive site to develop, and would be able to accommodate the pupils.
The new school plan is part of a £36m project in and around Ystradgynlais to close 10 primary schools and build four replacements. It also includes the £9.6m revamp of Maesydderwen Comprehensive School in Ystradgynlais.
The proposals were backed backed by Powys council in September.
Education Minister Leighton Andrews will decide if the multimillion-pound plan should go ahead and he is expected to make a decision at the end of March.
The action group, Say No to Brynderi, argue that the Welsh-medium school will be the largest of the four, but it will be on the smallest site and on land owned by a local football club, Cwm Wanderers.
The group also claims there will be smaller playing fields, outdoor habitats and nature areas at Brynderi in comparison to the three English-medium schools.
Members of the group handed a petition with more than 1,800 signatures to Brecon and Radnorshire AM Kirsty Williams at the Welsh assembly.
'Strength of feeling'
Spokesman Geraint Evans said: "We handed in a petition with more than 1,800 signatures. We also held a protest outside the assembly and about 100 people took part.
"We hope Mr Andrews will take into account the strength of feeling locally against this proposal.
"We feel this will be an acid test of the Welsh Assembly Government's Welsh-medium education strategy, which was launched last April."
A Powys council spokesman said: "The council carried out statutory consultation as part of its proposals to close 10 primary schools in the Maesydderwen catchment area, Ystradgynlais and open four new schools by September 2012.
"A report outlining objections and the council's response was considered by the board in January. The board agreed to continue with the closure proposals and submitted relevant evidence to the Welsh assembly for decision.
"It is hoped that a decision on the proposals will be received in the coming weeks."
The council said last September that the Brynderi site was the most expensive to develop, but it was capable of "comfortably accommodating" a 300-pupil school.
Powys council also plans to modernise its network of secondary schools, which has caused controversy in the county.