Ireland being a much smaller population have it easy to extend the mentality of being one big family.
Yes, I've always been aware that the smallness makes a big difference, although oddly enough class sizes are amongst the biggest in the EU.
I also think it's significant that although people are no longer such devout Catholics, and some are agnostic or atheist, most people still believe in God. Schools are under largely Catholic or Church of Ireland patronage and I think that makes a difference in the atmosphere/ethos of the schools.
Finally, I think learning the Irish language makes a difference. It's compulsory for all children from age four when they enter school to school leaving age. I think it helps to give immigrant children a feeling of 'Irishness' - that and the Irish sports, hurling for the boys, camogie for the girls, Gaelic football. The GAA (Gaelic Athletic Association) is a huge part of culture especially in rural Ireland and they've done fantastic work at integrating kids. Get them playing the Gaelic sports, speaking the Irish language, learning the music and you give them a sense of belonging.
Ireland is a unique place in many ways but I believe that much better integration could be achieved in other countries too. Where there's a will there's a way - and that's the bottom line really. If you start with a bad attitude, resentful, hostile or cold towards an ethnic minority, you reap what you sow. Children are part nature and part nurture. You can make a difference with children. You can create a better community for the future. And as more children come to school every year it's never too late to start trying.