CCTV footage emerged of a 17-year-old girl at Howth Junction Station falling between the platform and a stationary train on April 1 last year.
She was helped back onto the platform by her friends and staff.
Gardaí subsequently charged three youths aged 17 with violent disorder by using or threatening to use violence with two others, causing another person to fear their safety.
One of them had an additional charge for assault causing harm to the girl. He faced a preliminary hearing at the Dublin Children's Court in December.
The Director of Public Prosecutions directed "trial on indictment" in the Circuit Court, with broader sentencing powers.
Judge Paul Kelly watched the video footage and heard an outline of the allegations from Garda Kevin O’Boyle.
Refusing jurisdiction, he held that boy's case was too serious to stay in the Children's Court.
The teenager appeared again today to be served with a book of evidence.
His parents and solicitor Ellen Reid accompanied him to the proceedings.
Judge Kelly granted the DPP a return for trial order and told the accused he was being sent forward to the Dublin Circuit Criminal Court, where he will face his next hearing in March.
Following an application by Ms Reid, Judge Kelly granted legal aid to include senior counsel representation.
The Children's Court had heard that ten to 15 youths, "shouting and roaring", caused a disturbance on a train.
Security was dealing with them and prevented them from re-entering the train.
Six girls ran onto the platform to catch the Dart.
The then 16-year-old boy, who had a bicycle, allegedly used his handlebars to lunge at one girl striking her knee and "as a result, she fell down off the platform head first". A security man raised the alarm with the train driver and pulled the girl from under the train back onto the platform.
She had a cut knee and a bad cut and bruise on her back and was visibly distressed and in shock. The court heard she was in Leaving Cert year at the time and already suffering from anxiety.
Afterwards, it was difficult for her to go to school, where she would spend "most of her day in the toilet crying". However, her parents took her out before her exams, and she was getting help, the court heard.
The garda said she is on medication and “going through a difficult time”.
The court heard the group of youths were not known to the victim.
Refusing jurisdiction in the boy's case, he noted from video evidence that he "nonchalantly pushes his bike away" after he assaulted her, leaving others to help the victim.
He held that the two co-defendants had peripheral roles, and he allowed their cases remain in the Children's Court. They have pleaded not guilty and will face a hearing there in May.
All three remain on bail with conditions including no contact with each other or the girl. They cannot be identified because they are minors.