The aim was to do away with the mental block many students get when it comes time to studying maths. "The subject frightens people", said Prof. Vidal, "because of how it's approached and because it is not taught well enough. In primary school, mathematics should be a game where students feel like they are in charge. Mathematics should be functional and meaningful."

With this idea in mind, Salvador Vidal and the team of math department teachers at the Bell-Lloc School in La Roca del Vallès invented Number Day. According to Vidal, "We use a varied set of fun mathematics activities to get the students and the teachers at the school involved with the aim of encouraging them". In fact, because of the success of Number Day, it has been repeated each year and even exported to Santa María del Pino School in Alella.

Salvador Vidal is now a professor in the UIC Faculty of Education, where he explains the importance of mathematics and knowing how to explain the subject well. "Mathematics makes life easier; we couldn't live without it", he said. "In fact, some anthropologists say that numbers were invented before letters. It was a necessity. Early people made calculations (stone). Stones were their first calculators. When the men went out to hunt, each one left a stone at the camp entrance. When they returned, they picked it up, which told the tribe which men had not come back."

In this way, Prof. Vidal communicated the message, "Maths is always applicable. Some concepts are much more accessible and their applications are easier to see. But there are others that don't seem useful, but have applications in engineering and architecture. In fact, mathematics solves the problems that do not initially seem useful but an application is then found in the physical world".

This is the message now available from the book with more than 500 pages, Number Day: Mathematics Motivation, which was published in Spanish by Publicia.