The four-day event ended on Thursday.
The pupils were congratulated by Thai Talent Training project head Phumthep Khlang-urai upon arrival at Suvarnabhumi Airport on Friday night.
Ranchanat Rungrojnimitchai of Khon Kaen University Demonstration School won gold.
The silver medallists were Chaithat Tanprawat of Chulalongkorn University Demonstration Primary School, Panthat Kanokwaranont of Bangkok Christian College and Chaochon Rattanamangalanont of Chon Buri’s Chonradsadornumrung School.
The bronze medallists were Chanidapa Pitchayasaowapak of Chulalongkorn University Demonstration Primary School, Wachirawit Angkhathawanich of Bangkok Christian College, Panna Klankasem of Assumption College Rayong and Pat Poungkerd of Bangkok’s Panyarat High School.
A team comprising Ranchanat, Chaithat, Chanidapa and Wachirawit won a trophy in the Middle Primary Division team competition.
Another team – Panthat, Panna, Warich Cheusa-art of the Chiang Mai-based Prince Royal’s College and Rath-roj Thamrong-opas from Bangkok’s Amnuay Silpa School – won the second runner-up medal in the Upper Primary Division competition.