Athens College Junior High School student Kleio-Efrosyni Papanastasiou competed in the following championships:

• The Panhellenic Modern Pentathlon Championship, in the laser run category U17, held in Rafina on October 21-22, 2023 and won 2nd place.
• The Panhellenic Modern Pentathlon Championship, in the laser run category U19, held in Rafina on December 2-3, 2023 and won 1st place.
• The Panhellenic Modern Pentathlon Championship, in the Women's individual laser run category, held in Rafina on December 2-3, 2023 and won 4th place. 

The award ceremony was held on February 5, 2024, at the Hellenic Modern Pentathlon Federation's headquarters at the Goudi Olympic Complex.