Guernsey claimed two of the three titles in the inter-islands finals of the battle of the brains, but there was success for St Michael's Prep.
Hautlieu sixth formers and Year 8 students from De La Salle were narrowly defeated in their De Putron Challenge finals.
They both lost out to Guernsey's Elizabeth College.
However, St Michael's Prep were victorious, beating the Elizabeth College Year 6 team.

St Michael's were trailing going into the final round, but turned it around in the Arts and Literature section, winning the title by just four points.
Hautlieu, St Michael's and De La Salle were represented in the final after winning their heats in Jersey earlier this month.
Hayley De Putron, a trustee of the Ana Leaf Foundation presented the prizes and thanked everyone involved for taking part.
The Post 16 inter-island De Putron Challenge champions are... @Eliz_Coll! Well done to them and everyone who has taken part today. #DePutronChallenge #CoolToBeClever pic.twitter.com/5WD2oKpsdU
— De Putron Challenge (@DePChallenge) November 27, 2018

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