Teachers have lots of works to do at school, including making sure students learn mental, social, and academic informations. It is accountable for teachers making sure student advance, however, making their pupils write good papers, or get good grades in exams are out of teacher's hands. I think teachers should not be responsible for students do poorly in school.
 Firstly, there are so many factors that teacher can not control over their displine. For example, student may not have slept enough the night before the test, or caught a cold, and getting bad grade for the exam. Unexpected elements can affect their student's grades, and teacher can not control such inconsequential proxy, and even if they can, the students would be unpleased about how teacher intermiddle in their lives.
 Next, personally, I think teachers are not the one who want students have a bad grades or not. However, the parents do. In my opinion, the parents are responsible for their children, which would be students for teachers, not teachers. In my childhood, My mother looked over my homeworks, made me to solve my math problems, and had me to read to her in English. when she could not explain something to me, my mother involved my teaher.
 Though some people think that it is teachers should hold responsible for students get bad grades at school, I think they have no responsibility for poorly performing students at school, whereas there are considerable amount of factors in students's life that teachers can not catch, and it is parents' s responsibility to do so.