A team from the University of Granada in Spain took a P300 brain-computer interface into a secondary school classroom, using a Bitbrain Versatile EEG system to identify a digit a volunteer had silently chosen, in front of nearly a hundred students. The demonstration grew out of a thesis by industrial electronic engineering student Marta Rodríguez Comino, supervised by Dr. Joaquín T. Valderrama and Dr. Iván López Espejo. The water-based portable EEG system decoded the attention signals using principal component analysis and a support vector machine.