That sounds better than a good portion of my K-12 math education. Starting in 7th grade and going to 10th grade, I would walk into class and the teacher would have a list of problems on the board for us to complete and turn in. That's it. Zero instruction at all, we were expected to read the book to figure out how to do everything on our own because the teacher barely knew how to do the problems. These were the "upper level" math classes too.
This situation was actually pretty terrible. My classmates and I hated this setup and most of us were barely learning the material, those of us who did figure it out usually had to teach those around us since the teacher wasn't. During this time my math grades were low compared to my normal grades, mostly in the B to D range.
Eventually, I found a teacher who would spend class teaching instead of having us work on "homework" the whole time. We would go over all of the relevant theories to the chapter for a few days, showing us, in a way that most of us could understand, mostly how they worked but without getting too in depth. At this point, I went from being the guy barely skating by in math classes to being a straight A student, just because my teacher was willing to put in the effort.