If you feel this way, politely express your concerns to your teacher. Your teacher may not necessarily realize the effect he or she is having on the students. The situation will not change unless the teacher is made aware.
In my short teaching experience thus far, I have noticed that the abilities of the students year to year has been decreasing. What I mean by this is the capabilities of my first ever class of 11 University Preparation students were capable of doing a number of things that, according to curriculum, they should have known and understood well before grade 11; the following year, the same grade level knew less, and the year after that the students knew less than the second group, and so on, forcing me to go back to basics before I could teach new concepts. This happens with every group I teach, regardless of grade or level. Teachers expect students to know and understand certain concepts before the students get to a certain grade/class, because, according to curriculum, they should have already accomplished certain tasks; unfortunately, however, this doesn’t always happen, frustrating the teacher who is trying to fit in everything they are required to teach (which is a lot!) I am not trying to excuse your teacher’s comments, as I can understand their effects, but what I am trying to do is explain the perspective of the teacher for expecting certain things from students.
Please talk with your teacher.
Teaching In Real Life 