It follows protests from some parents who claim their children are lagging behind in English, some by as much as 18 months. One Welsh-speaking parent has withdrawn her two children from Ysgol Betws-y-Coed, Conwy, saying it has not fulfilled its bilingual obligations towards English.
However, moves to introduce more English have upset other villagers in Betws-y-Coed, who say the school should remain loyal to the Welsh language.
Estyn judged Welsh the weakest of six subjects at the school.
Penny Richardson, 32, decided to find another school for her children, Roxy, nine, and eight-year-old Chloe, after clashing with the school over its language policy. A Welsh-speaker, she has lived in the village all her life.
In the meantime, the local education authority and school governors are trying to thrash out a solution acceptable to all parties. Governors and staff at the 86-pupil school met on Tuesday night.
They plan to update parents in letters, and consultation meetings with parents are planned for a later date.
Lessons at Ysgol Betws-y-Coed, which also serves the nearby village of Capel Curig, are supposed to be held in both Welsh and English. However, most of the core lessons, including maths and science, have been taught purely in Welsh. Just 12 per cent of pupils at the school are from homes where Welsh is the first language.
According to Dilwyn Price, Conwy's assistant director of primary education, there is consensus that the school should introduce more English. But the move had met some opposition.
Mr Price said the school was working on communications with parents, adding: "This is a highly emotive issue which could prove very divisive - we want to sit down and find a solution."
Betws-y-Coed councillor Liz Roberts said: "What is needed is for everyone to sit down and find some balance. Possibly there is too much Welsh at present."