Ireland ranks second among the 41 wealthiest countries of the European Union and the Organisation for Economic Co-operation and Development at reducing educational inequality, according to UNICEF.
Despite the positive findings, the research 'An Unfair Start: Inequality in Children's Education in Rich Countries' says substantial gaps still exist between the best and worst performing students.
There are concerns that vulnerable groups such as Traveller children, children experiencing homelessness, and immigrant children are in danger of being left behind due to insufficient educational supports.
The ranking results for Ireland show that inequality among children decreases as they move from early childhood education (33rd) to primary school (16th) and on to secondary school (2nd).
However, with one in ten students not reaching basic proficiency in reading by secondary school (age 15), a large minority are still falling through the gaps and not getting the resources they need.
Ireland, Latvia and Spain are the most equal when it comes to reading ability among 15-year-olds.
UNICEF Ireland Chief Executive Peter Power said the latest report card shows that Ireland can lead the way when the right funding and polices are in place.
He added: "However, we are concerned that some of the children most in need, be they from vulnerable groups such as Traveller children, children experiencing homelessness or immigrant children, or those children living outside of the DEIS support system, are being left behind.
"In Ireland, around 86% of the inequality in reading scores is between children within schools, and only a small amount is between schools.
"This means that while our schools produce good results for the many, there are some children, and often those most in need, who are falling through the gaps.
"We need to ensure that every child has the right wraparound supports they need in school to achieve their highest potential."
Speaking on RTÉ's Morning Ireland, Mr Power said the most vulnerable groups of children need targeted approaches to help them.
"How do we address the bottom 10%. They all need targeted approaches. And yes we have systems and strategies in place for them but there is no reason why Ireland cannot become a more equal education system.
"Our system is only as strong as its weakest link so we have to invest in supports and systems for those 10% to make our system more even for the future."
