This year students of Athens College Grades 8 & 9, members of the Mathematical Thinking Club, travelled to Barcelona to visit the Mathematical Museum of Catalonia (MMACA) and the Cosmocaixa Science Museum. During their visit to the Museum of Mathematics, our students worked in teams to build Leonardo's self-supporting domes, toured the rich collection of exhibits, tried to solve puzzles and experimented with real-life applications of mathematics. At the Cosmocaixa Science Museum they watched the Sapiens exhibition and visited the other interactive exhibits. Students toured the city learning about Gaudí's architecture (La Sagrada Familia, Casa Batlló and Park Güell).