Drawing is a little hard

I am taking an intro drawing class. I am quite average in the class. This is bad because I need to get a B or A in order to count it toward my requirements. But, it is also good because it is because we have Art History majors (and an art hist prof on sabbatical auditing) and photography majors, and 2 Theater Arts majors. They really could be taking the art for non majors version, I am not sure why they are in 20A rather than 80A, except that 80A is certainly very full.
This is a subtractive drawing, where you give the whole page a midtone with charcoal, then try to get everything else lighter and darker. Class ended before I finished the highlights on the right one, but I will finish it for my Final Portfolio.
I am really impressed with this one. It is sort of the same, you start with black paper and you add in the highlights. I think highlights are much easier to see and record than are shadows.

And then, right when i was getting the hang of still lifes, we had to start landscapes. Mine is a little wavery and undefined, but I am fairly happy with it.
We had to do pen and ink + inkwash landscapes. I picked an over manicured lawn, so there was not really anything to draw, until the shadows started lengthening. I occupied the time by inventing various paintbrushes, such as this one made from grass and a kneaded eraser.

So, on the whole, art class is not going very well. I enjoy it but I have a hard time working from whatever thing is handy rather than working on specific finished projects that catch my interest. I also have noticed a weird range of ability, that seems uncontrollable. Sometimes I can do very precise work, and sometimes I feel like I will never be good at drawing or enjoy certain techniques. We are doing manual grid enlargement and distortion right now, and i think i might scrap my enlarged ink wash tonal portrait. A lot of people are making almost photographically precise enlargements, thanks to the grid, but I for some reason can not. My re do is going to be in charcoal, because it is a little easier to work with.