The "baptism barrier" in schools will be officially removed today.
It will ban the use of religion to select which children are admitted to primary schools as before today, schools - which are mostly of a Catholic ethos - were allowed to prioritise children of their own faith ahead of those living nearby as part of their admission policy.
That will no longer be the case when the Education Minister Richard Bruton signs the commencement order later for a new law to take effect.
The changes will affect oversubscribed primary schools, mainly in urban areas, where places are limited.
Other changes in the legislation coming in today include the ending of admission fees and a cap on the number of children or grandchildren of past pupils a school can enrol.
Meanwhile, a new P.E. programme for Junior cycle students is aiming to get 200,000 Irish teenagers more physically active.
DCU and the Irish Heart Foundation are behind the initiative, with research showing that only 1 in 5 teens are getting enough exercise.
A training programme is being offered to P.E. teachers to implement the new approach that makes classes more enjoyable and engaging.
Dr Sarah-Jane Belton from DCU, who is one of the designers of the programme, says "physical literacy" is vital for kids.
"It's about the health and wellbeing of the child, and enabling them to develop the skills they need to be physically active, things like motivation and confidence.
"If we get that right for our children, the outcome is physically active kids, the outcome is active adults and the outcome is healthy adults," she said.
In Dublin today, attendees of the Learnovation conference will hear about how teachers could soon be marking their students' homework using voice messages.
Abdul Chohan, one of the pioneers of the idea and the founder of the Olive Tree School in Bolton, says students at his school upload their homework on their tablet, and get personal feedback from teachers.
The technique, using iPads, has already been successfully introduced in schools in the UK.