Hermon primary, in Pembrokeshire, was served with a closure notice on June 18. The authority intends to transfer pupils to a new, larger primary which will open in a nearby village in September 2004.
Pupils plan to challenge the county council over the decision-making processes which they say were invalid. As they have no income, they qualify for legal aid which will be used to hire a barrister.
Luned Nicholas, nine, said: "I want to go to court. I won't like the new school, because I'll have to make new friends, and there will be new teachers."
John Davies, Pembrokeshire Cabinet member for education, believes that a judge will uphold the council's decision.