in these videos you get to show acts of tranquilisando teachers to their students after some shootings.
Here we we realize that there are teachers who even after all try to remain calm.

                                     meaning master

A teacher (Lat. Magister) is someone who has studied teaching and is responsible for the formal and institutionalized children in kindergarten, primary and special education in schools or colleges. Some teachers may be aimed at secondary schools in social security programs, remedial education or support for pupils with special educational needs, as well as centers of Adult Education.

A teacher is generally address the basic education of pupils in compulsory basic education to 3-16 years. If these students have some type of special educational need that age can be interleaved.

The qualifications that a teacher must hold for the exercise of their profession is the college graduate (depending on the country, three to five years of higher education). Until recently the colleges of Education in Spain were called normal schools, a name that still stands in France and much of Latin America. Normalism originated in the US. UU., And it could say that was a solution to the intense existing illiteracy. It parallels with the barefoot doctor in China.

other works of masters

As synonymous with Sensei, a Japanese title to refer to teachers and authority figures, whether martial arts, or some other discipline
As synonymous with Guru, a master of Hinduism, Buddhism and Sikhism.

In some religions and spiritual traditions the master term for spiritual guidance is used. In particular those used for notable historical figures who gave teachings that lasted over time. Examples of these figures are Jesus, Buddha, Muhammad, Confucius and Lao Tse, who besides being spiritual leaders and teachers were left teachings. Often these teachers had a group of monks who traveled and lived with their leader and teacher.

In various arts and crafts like music, architecture, dance, literature, painting or masonry, spirits tasters and blenders etc. who produces works that transcend after his death; it is customary to also call master

In some philosophical institutions and philanthropic associations, the term teacher refers to a symbolic, hierarchical level that is also related to transcendence post mortem. For example, in Freemasonry, there is a degree of master that is not unlike the master degree that transcends death by his students, see Master (degree).

In chess, a Grand Master, he is a player with great degree of skill in this game. An International Master is a player who gets a certain Elo and meets certain requirements (collection of standards). Both titles are international. Below them is the Master and FIDE Candidate Master.