She claimed the school unlawfully excluded Trival after failing to let a social worker attend what she thought was a meeting to discuss his special-education needs.
"I thought we were going to this meeting to put an action plan in place, I didn't realise we were before the board for an exclusion meeting."
Youthlaw spokesman Ben Mills said Trival was one of many students who felt unfairly treated and were kept out of school for months.
"It was illegal to turn away the social worker ... it is courtesy to let the school know they are coming, but that is no justification to breaking the law, you can't turn people away," Mills said.
Youthlaw had been compiling a comprehensive report supporting a plea to the Ministry of Education for an appeals tribunal for students unlawfully excluded. The 41-page report said New Zealand was lagging behind England, Australia, Canada and South Africa.
"This appeals tribunal would guarantee that no student in New Zealand is deprived of their fundamental right to an education without normal justice," the report said.
Figures obtained by the Herald on Sunday showed two students excluded in 2009 had still not been enrolled with a new education provider. More than 1000 students were out of school for at least one month, and 69 students were out of school for at least nine months following exclusions.
Ministry group manager Jeremy Wood would not comment on an appeals tribunal, but said there were other options for students.
"Families of students excluded from school can appeal to the board of trustees in the first instance," Wood said. "If they feel disciplinary procedures have not been followed correctly, they can contact the Ombudsman or they can take the case to the High Court."
Gestro said her son was accepted into Papakura South School this week, but she still wanted to appeal the exclusion.
"There are other children out there and we don't want them to go through what we have gone through."
Mansell Senior School did not return calls for comment.
