St. Joseph Calasanz is not the exclusive property of the Piarists, nor do the nine Religious Institutes exhaust him.

In 1945, the Spanish Teachers Asscociation declared him as their patron.

Three years later, in the third century after his death, Pope Pius XII declared him "Patron before God of all Christian Public Schools in the world." That is why he is called the Patron Saint of all elementary and secondary schools.

Argentina passed Law No. 13363 which declared him to be the patron of their primary and secondary schools.

In Spain, he is patron of the C.S. Institute of Scientific Investigations, the Pedagogy Faculty of Salamanca University, the Madrid Sciences Education Institute (ICCE), and many other schools both within and outside of Spain.