Forty-five tickets for the group match at St James' Park on 18 September were bought by the High School of Dundee - days after 110,000 fans had been in an online queue for the remaining seats.
A school spokesman said the school purchased the tickets in good faith after being "approached".
But it is understood that the tickets came from unauthorised reselling by fans who have now had their season tickets cancelled.
A Newcastle spokesman said: "These tickets will be made available to Newcastle United supporters through the club's existing ticket sale process."
A similar number of students from the school attended Newcastle's most recent Champions League game, against AC Milan in 2023.
A spokesman for the school previously said the tickets were "bought as part of a group package".
But Newcastle do not have an authorised reseller and the only way to sell season tickets is through the club's official platform at face value.
www.bbc.co.uk
A school spokesman said the school purchased the tickets in good faith after being "approached".
But it is understood that the tickets came from unauthorised reselling by fans who have now had their season tickets cancelled.
A Newcastle spokesman said: "These tickets will be made available to Newcastle United supporters through the club's existing ticket sale process."
A similar number of students from the school attended Newcastle's most recent Champions League game, against AC Milan in 2023.
A spokesman for the school previously said the tickets were "bought as part of a group package".
But Newcastle do not have an authorised reseller and the only way to sell season tickets is through the club's official platform at face value.
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