In two classes we visited, the high level of content offered stood out. In secondary school (pupils of 15 years and older), the geometry class was staggeringly new to me. It is called geometria descritiva here. Now, my experience with geometry is over 40 years old, so I understand things have changed. But in this class student are requested to draw a pyramid shaped form, from three perspectives on one sheet of paper. And it is not the pyramid of Giza they need to draw, it is oblique and upside down. This is not just geometry, it is a preparation for architecture and technical drawings.
The students heftily confer during their assignment, much to the teacher’s John (João) discomfort. This class is too loud. But very busy with their task, so the noise is not disturbance per se, it is learning in progress.
That this content is difficult is well known by teachers. Most students follow extra classes in the afternoon, after school. Their parents stimulate or make them do that.
Extra classes on geometry are offered everywhere
During a biology class, to 11 year olds, the subject was heart, lung and vascular system. Again, high level content for young students. Quite different from what we teach in the Netherlands.