Parents have been warned not to let their children absorb the parents' stress during the rush to get out of the house in the morning.
As some 51,000 children headed to school for the first time yesterday, Ms Finnoula Kilfeather of the National Parents Council said children could detect their parents' anxiety.
"Of course children can pick up on it. We would be advising parents to stay calm in the mornings, make sure the children have had a relaxed breakfast and are out of the house in time. There is nothing more stressful than being hassled by your parents when you are already more than a little worried about starting at school.
"The vast majority of children like going to school these days but the odd one doesn't and parents should talk to the teacher earlier rather than later. You will get the occasional child that doesn't settle and parents shouldn't be afraid to approach the teacher about that as soon as possible," she said.
Ms Kilfeather said the new junior infants often coped better with the first day at school than their parents.
"It's a big day for parents whose children are starting for the first time. We have had loads of them ringing us up saying they're in bits while the children seem quite callous. Quite a lot of them feel like they're losing their babies," she said.
Ms Kilfeather said she could only comfort parents by telling them many others were experiencing the same emotions, and encouraging them to talk about their feelings to other mothers and fathers.
The early-morning scramble to the school gates added to traffic on Dublin's main roads which were chock-a-block from an early hour.
In Galway the roads were badly blocked, and in Waterford traffic was brought to a standstill on the Cork Road and Dunmore Road.
