Having a large class group demands a different approach and more strategic methods from teachers.
Whether or not, the strategies on the youtube video could work in our country depends on how well we can reach a sustainable adaptation, plus considering the expected reaction from students.
On the video we were able to get a glimpse of the students' behavior, they were children. The class dynamic seemed fast-paced, the teachers had pretty clear fluency. The one who wasn't of american origin, talked about the use of multimedia. Another one, advised to display the students' work on the classroom's walls.
Basic points such as having respect, giving rewards, and not humiliating anyone, need to be taken into account, no matter the age or level. It is only the language, methodology or topics, which require adequate changes according to each specific group we deal with.
An effective tip for teaching large groups, is simple but also witty. We can provide individual attention to each student or group, by taking a few days, and avoid attempting to attend everyone in only one class, for it's almost impossible, not to even mention, exhausting...
When having the classroom physically organized, allowing students to move around the class, was brought up, it was hard not to think that in our reality, we aren't very likely to enjoy the benefits of much free space, since the classrooms tend to be small.
The one part I thought is generally the same in El Salvador, is setting up classroom logistics. Most teachers I know do plan their activities, follow determined patterns, organize students, etc. In that regard, there's not much difficulty to be faced, but of course, preparation time is required.
Maybe "being proactive" is not so common in our country, and it should not be that way. Nevertheless, it is in fact, understandable. Lots of teachers aren't proactive due to the lack of motivation they have, with low salaries, poor conditions, etc. And besides, students aren't keen to plan their own activities and seriously consider pedagogical issues. But perhaps through playful means we can try to change these paradigms.