Pupils from Ysgol Ifor Bach in Abertridwr won first prize for the best banner displayed in a parade to welcome the Urdd Eisteddfod to Caerphilly County Borough.
Around 4,000 children and adults took part in the Proclamation Parade held on October 4.
The school will now receive a prize of £500.
The Eisteddfod will be held in the grounds of Llancaiach Fawr Manor near Nelson, between May 25 and 30 next year.
Aled Sion, Director of the Urdd Eisteddfod said: “We had a great day in Caerphilly on Saturday with a great number of local children joining in the parade to announce that the Urdd National Eisteddfod is coming to the Caerphilly area. The enthusiasm here is outstanding.”