So I (21M) go to college, taking up engineering. I befriended a classmate of mine who struggled a lot because he is a foreign student. He is currently taking up Differential Equations and its his last attempt. He failed Differential Equations twice and my college's policy is that you can only take a subject three times. If you fail in all three times, you are out. So the start of the school year was in August and he saw the teachers for Differential Equations. One of them was my former teacher. That teacher was actually pretty good, and I recommended it to him. He then applied for it and got approved. However, my classmate later chatted that the passing rate for the subject is a whopping 75%, before it was 50%. I get the feeling this is my fault because I have heard from some students that the other teachers have been more kind and understanding compared to my previous teacher.