Students from Jersey College Prep and Victoria College will represent Jersey in the final of the De Putron Challenge.
The teams from years 6 and 8 won the local heats of the schools quiz and will compete against Guernsey's top teams next month.
Trinity and St Michaels were runners up.
The other schools that made it through the heats to the Year 6 final were FCJ Primary School, Bel Royal Primary School, La Moye Primary School and St George’s Preparatory School.
They answered questions on nature, history and current affairs, and were tasked with making a catapult out of wooden lolly sticks, rubber bands and a spoon.
Every pupil who took part got a £10 book voucher, and the top two teams in each year group won money for their school.
Hayley de Putron, a trustee of the Ana Leaf Foundation and founder of the de Putron Challenge, said: “Congratulations to Jersey College Preparatory School and Victoria College for winning the challenges in their respective year groups. Every year I am consistently amazed by the depth of knowledge displayed by our young islanders. Every team gave their all today, and I trust that their peers and fellow competitors all gained valuable insights and lessons from this experience.”
The Guernsey heats take place on 12 March, with the inter islands final at the Royal Jersey Showground on Thursday 21 March.