Ferreira took part in the race, which comprised a 750m swim, a 16km mountain bike ride and a 6.4km trail run, and won a silver medal for his efforts.
John Skelton, principal at the school, congratulated Ferreira on his impressive achievement at the championships.
“This is a remarkable achievement and we look forward to many more achievements from this young man,” he said.
The championships took place on 26 September in Sardinia, Italy.
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