Fiona Darragh's eight-year-old son, Harry, attends the special needs unit of Knockmore Primary School in Lisburn.
The mainstream school – where one in three pupils are catered for in special units – had enrollment of 153 in 2012/13.
But a question mark now hangs over the school's future. The South Eastern Education and Library Board has listed it as one of the primary schools where a "local area solution" is to be explored.
It highlighted the school's 2012/13 enrollment as 96 pupils, which is below the minimum threshold set out in the Department of Education's Sustainable Schools Policy.
It is the third time that the school's future has been threatened.
In 2011, the South Eastern Education and Library Board (SEELB) told staff and parents that it was considering publishing a development proposal recommending the closure of Knockmore Primary School, with effect from August 31, 2012.
Yesterday, Fiona Darragh, chairwoman of Knockmore Working Group, said the department's failure to include pupils who attend the school's special needs units was "hurtful".
She said: "I find it insulting that children like Harry are excluded. Are they trying to say Harry is a second-class citizen?" she asked.