In Ireland, there are areas where the Irish language is spoken exclusively, these areas are called Gaeltacht. Students living in those areas speak Irish both at home and at school. But outside those areas, schools teach in the English language. This is changing due to Gaelscoileanna. Now students who are speaking English at home and in the neighborhood are being taught in Irish at school. Additive bilingualism occurs in students attending Gaelscoileanna since they are immersed in both languages on a daily basis. This has shown to have positive impacts on mathematics learning. Other countries, such as Wales, Scotland, and Canada, have implemented similar types of schools. Research on Irish-medium language immersion programs effects on mathematics education is presented.