The Department of Education state that children can start national school between the ages of 4 and 6 years of age. Some schools are very keen to take a child at 4. This can be because they want to beef up their numbers if they are trying to secure an extra teacher. Other teachers are not keen and suggest a child should be a good 5 years of age. You can find the school one direction will take the child and the school in the other direction is not so keen. I lived in the UK for many years and the system in my opinion was much better. All children are 4 years of age when they start and they seemed to have a much better set up in place. They appear to have a much better handle on their numbers and much better structures in place. Ireland is lagging behind in my opinion.