One of the main problems my school has is that we have to many students and not enough teachers, but they can't fix this problem without money. Some of my classes have upwards of 30 students, when ideally, one class should not have more than 15.
To compare, I'll use my Math class and my English class. In Math, where we have 34 students, the teacher is constantly bombarded with questions by at least 10 different students, because they don't understand the various ways we are being taught how to solve the problem. We go through this process 10 times in a class period, each time we have my math teacher explaining how to do it in a different way, literally covering all angles before we can move on. Sometimes the lesson isn't finished before the bell rings, causing us to have homework where we occasionally aren't sure how to solve some of the last few problems. Our teacher doesn't know half of our names, and is never sure which students have problems learning in what way. He's trying his hardest, I can tell that, but some of his other classes have close to 40 students and it's hard to keep them all straight in his head.
English, however, has a class with 13 students in it. His other classes have about the same amount. My teacher knows all of us by names, and even by nicknames. When we start class, there are two students that learn best in a different way than the rest of us do. Our teacher noticed this and Incorporated it into his lessons. When it's hard to incorporate it into the lesson, he'll teach the majority way first and then go help the two others individually their way. It's a much tighter-knit class where everyone succeeds, and most of class has test scores in the 97th percentile or above. But I do not feel as if our teacher is teaching us to the tests, as he keeps things very hands on, lets us write about fandoms, considering I turned in at least 5 assignments where I talked about Mother 3, asks the class whether we want to move on to Shakespeare or stay on the poetry unit, because he knows that we can get through Shakespeare pretty quick if need be and saw how the class loves reading poetry. Grammar is Incorporated in to free-writing assignments, which allows individuals to be more creative. I can go on about how I like how he teaches, but that would take too long.
The main difference here is how many students they have to remember. My math teacher has too many students to keep track of, which doesn't allow him to personally connect with any of them, while my English class is more personal, and my teacher understands exactly what each student will be able to do, and how they best learn.