It is quite obvious that when the students are in very large numbers in a class, the teacher cant pay individual attention. I think as far as students are attentive in the class, teachers attention to individual hardly matters. Not all students in a class need personal attention, because they are smart and grasp the lessons quickly by themselves. However some of the students who are a little weak can surely get personal attention of the teachers.
Nevertheless for the teacher to be able to monitor progress of all students of a class, it is necessary that proper student teacher ratio is adhered to. Student-Teacher ratio refers to the number of teachers in a school or university with respect to the number of students who attend the school or university. For example, a student teacher ratio of 10:1 means that there are 10 students for every one teacher available. The term can also be reversed to be teacher-student ratio. If one classroom has a 30:1 ratio and the other has a 10:1 ratio, the school could claim to have a 20:1 ratio overall. But if the ratio is 50:1, the school needs to hire more teachers. In a way 40:1 is the ideal ratio where all students can get proper attention of the teacher.
Summarizing, this is the responsibility of the educational authorities to inspect schools and universities periodically to ensure a right student-teacher ratio and in the event of this ratio changing due to greater number of students, educational authorities must strictly advice schools to hire more teachers and maintain appropriate student teacher ratio. This shall help all students get better attention of the teachers if not individual attention.