Parents of more than 100 sixth class pupils in Rush have been told there will be no places for them next year in the local secondary school.
There are 104 students currently on a waiting list for places in St Joseph's Secondary School in the coastal village.
But with a shortage of places in the school, many pupils are facing the prospect of long commutes to schools in other areas next year.
Associate secretary of St. Catherine's National School Parents Association Katie Wallner said she did not believe 12-year-olds should be commuting long distances to school.
In a post on the Local Parents for More Secondary School Places in Rush Facebook page, she said: "I strongly believe that 12-year-olds should not commute for several reasons.
"One reason being the poor public transport and the fact that very few Fingal Schools have School Bus service from and to Rush.
"The other reason is that the secondary school studies are way more demanding than primary school studies, with more homework, possible extracurricular activities and so on.
"Also, teenagers are always tired and it is quite normal.
"They have huge changes in the body, they need time to relax, walk, listen to music, hang out with their friends and not to waste their time on crowded buses or trains."
The parents have been told that the school is seeking approval for a temporary building to allow it to take in more students.
Dublin Live has contacted the Department of Education and Skills for comment.
