Gretchen6, I don't think there's any hope for a happy, Hollywood ending in this movie "La Lengua de las Mariposas". These prisoners being hauled off in the back of that truck - including the boys teacher, are being taken to their execution or to years and years in jail.
I think it's left up to the viewer to wonder if the boy, Moncho, TRULY turns on his teacher because "the mob" is shouting all the same things like "¡ATEO! ¡PAYASO! ¡ROJO!" or is he doing it to "protect" the ideals of his own family? His own mother instructs Moncho to shout these things in order to publicly deny any possibility that the family believes in the ideals of these "Rojos" (and remember, people were labeled such if they were entertainers, gay, educators, artists, and, well, those who verbally shared their counter-government-related-ideas publicly) even though the father held these same ideals but (so far) was not found out and labeled as one of "them". Yet. These acts of rounding up people was a strong statement to others that they SHOULD follow/support the current government (Franco's dictatorship) or suffer the consequences.
Remember, this is a small boy and doesn't likely understand the politics surrounding him so he does what he's told and believes the things that the people around him believe - whether right or wrong.
In the movie, we see Moncho's teacher (in the classroom) giving a speach when being honored for his lifelong dedication as a teacher. In that speach, the teacher pronounces how animals/insects (I think) were born to live free, etcetera. This speach has strong anti-government overtones and one of the attendants, a powerfu, rich businessman (the father of one of the students) storms out of the room.
So "en fin", no, I don't think Moncho mixes-in any positive things to shout at the teacher while running behind the truck and throwing stones with the others. The heart-breaking look on the teacher's face as he watches his favorite student, who was like his only son, shouting these things at him is powerful. I get tears everytime I watch it.
On another note, I can't believe I STILL haven't seen "Mar Adentro"! I'm waiting to get/see it on DVD so I can view it with English subtitles.
Saludos, MadridMan