Judgment of the Court (Second Chamber) of 21 December 2023.#Scuola europea di Varese v PD and LC.#Reference for a preliminary ruling – Convention defining the Statute of the European Schools – Article 27(2) – General Rules of the European Schools – Articles 62, 66 and 67 – Challenge to the decision of a Class Council not to authorise a pupil to be promoted to the year above in the secondary school – Lack of jurisdiction of the national courts – Sole jurisdiction of the Complaints Board of the European Schools – Effective judicial protection.#Case C-431/22.