This can work for other things, such as chemical experiments. I also do not not like to sit by the windows because of the cold. I can't concentrate because of the many distractions. The problem gets worse when the teacher explains to a large number of students because we cannot understand the lessons. The spread of contagious disease among students, as well as rheumatism and backache due to awkward sitting postures.
Some students force others to sit on chairs in the back of the classroom or on the ground.
Mixed together, older students try to dominate younger ones. Overcrowding obstructs teachers from classifying students according to their ages or conditions such as near-sightedness. Some students sit on different chairs from the standard school desks. This could cause envy among students. Some parents are asked by the school management to bring chairs and tables for their children.