No matter how good your teacher is, learning a new language is something you will ultimately have to do for yourself. Nobody can simply log into your brain and install new words and grammar, and even if you diligently complete all of the assignments in a language class — even if you get a good grade — it’s still entirely possible to finish without actually improving your ability to speak that language by more than an infinitesimal fraction.
Thus, you ultimately have to be your own teacher. Pay attention to what does and doesn’t work for making new information stick, and which words you contantly have to look up over and over again. Also notice which topics you can already speak relatively fluidly about, versus those where you still have to pause and hunt for terminology or consciously construct sentences, and then concentrate your practice on the areas that you have trouble with. Simply following a teacher’s instructions as to how to practice your language is better than nothing, but more often than not, you will end up wasting a lot of effort on strategies that don’t work for you.
It’s also worth remembering that the grade or other evaluation you receive from a class may not be indicative of your actual ability. This can swing both ways, and you should be on the lookout for both possibilities (either the grade being significantly better than what your ability would warrant, or vice versa). I personally will often get good grades in upper-level language classes while still having very poor listening comprehension (especially when recordings or any sort of noise are involved), since most exams are written and even explicitly oral exams are generally given by careful speakers in idealized sonic conditions.
Even if you have had great experiences with language classes so far, it can never hurt to invest some time in studying the language on your own outside of class. You might discover something that works even better than what you’ve been doing in class, or at the very least simply get ahead.
Chasing Monotony 