Enoch Burke stood outside on the grounds of Wilson’s Hospital School for several hours on Wednesday, a day after he was arrested by gardaí under public order legislation.
Shortly after 8.45am, Mr Burke was dropped to the Co Westmeath school by his father, Seán.
Mr Burke walked to an entrance of the school building, but was denied access. Mr Burke then remained outside the building for several hours, until the school day ended, after 1.15pm.
He was collected again by his father and driven away.
Mr Burke was dismissed from his position as a teacher at the school in Multyfarnham, Co Westmeath, last Friday.
Under school disciplinary procedures, he is entitled to appeal the outcome within 10 working days.
Mr Burke last week failed in his attempts to get a High Court injunction to prevent the disciplinary hearing from taking place. He argued that the process had “gone irredeemably wrong”.
He had been suspended and on paid administrative leave pending the process, initiated on foot of a report prepared last August by the then school principal Niamh McShane.
It concerned Mr Burke’s emailed objection to a direction last May to teachers to address a transitioning student by their chosen name and using the pronouns “they/them” and his publicly voiced opposition to that direction at a school event last June. He alleges such a direction is a breach of his religious beliefs.
Gardaí said that a man had been arrested on Tuesday before being released “pending the submission of a file to the Office of the Director of Public Prosecutions”.
Speaking to reporters at the gates of the school, Mr Burke claimed that he was “wrongfully” arrested and described the incident as “reprehensible”.