Starting with your arrows, these definitely flow really nicely, but one thing I am noticing is that if you look at the rate at which the width of your ribbons get narrower as they move away from us, and the rate at which the overall space (the lengths of the ribbon, the distances between the zigzagging sections) compress, perspective is not being applied consistently across the board. This is a pretty common mistake - when tackling this in the future, or thinking about perspective in general, be sure to have perspective compress your negative spaces at the same rate it compresses the positive space of your objects.

Moving onto your organic forms with contour lines, you're definitely making a good effort to maintain simple sausages, as described in the instructions. I am noticing however that while your contour ellipse sausages are generally pretty well shaped, the contour curve ones have a tendency to get a little pointy on one end, where that end (which ought to be more "spherical" gets stretched out.

Additionally, keep in mind that the degree of our contour ellipses and contour curves corresponds with the orientation of that particular slice of the form in space, relative to the angle the viewer is looking. As we slide along the length of the form, this will change, with the degree correspondingly getting narrower or wider - either as that slice is more visible or less visible to the viewer, as shown here.

Continuing onto the texture analysis, I think you've definitely got a good start in terms of how you're focusing largely on the use of shadow shapes. To this end, one thing that can help with those bits further to the far right side (where you did still end up drawing lines) is to approach things as explained here. Basically, instead of drawing any lines, treat everything (even the narrowest line) as though it is a shape. First outline it, then fill it in.

Secondly, remember that the result of all of these shapes is always going to be some form casting a shadow onto another surface. If you look in your third row there, you ended up filling the negative space between the big forms, but this isn't technically correct - shadows are not liquid, and they do not fill spaces. Instead, you need to be thinking about the specific nature of the shadows those forms would cast on their surroundings. The difference here is quite minute in terms of the result, but the mentality that goes into how you draw it changes fundamentally.

Lastly, what you do need to continue to work on as you move forwards is how much attention you pay to the actual reference images. These photographs are packed full of all kinds of little bits of visual information, with all kinds of little textural forms that are present. Right now it does seem that you're still largely relying a fair bit on your memory - you'll look at your reference, try and record what you see, and then go to draw a bunch of it. This results in your brain focusing on a very limited range of the information it saw, tossing out the rest, and in turn creating a simplification of the result. Right now your brain isn't well trained to simplify things in a useful, meaningful way, so it tends to throw aside a lot of information that is actually useful. The best way around this is to purposely spend more time observing your reference, looking away only long enough to draw a mark or two, to establish a specific cast shadow and imply the presence of a certain form, before going back to refresh your memory.

This largely stands for your dissections as well - they're moving in the right direction, but there is plenty of room for improvement in paying closer attention to your reference images. Also, with any textures that are made up of very specific, individual textural forms (like scales, kernels of corn, etc.), you still have a tendency to outline each and every such form in its entirety, closing off any way to actually transition from one level of density to another. To this point, give these notes a read.

Your work on your form intersections is in large part looking pretty good. Your linework's pretty solid (a few ellipses are a little on the looser side, but still they're pretty decent), and while some of your boxes are a little wonky (don't forget that when constructing these, you need to keep thinking about how you're getting sets of parallel lines to converge consistently in the same direction - anything else is a distraction that will throw y ou off), you're drawing your forms such that they feel cohesive and consistent within the same space.

What I am noticing however is that when you attempt the intersections themselves - which is just something we're introducing here, and which I don't expect students to have any experience with whatsoever - you have a tendency to just draw more line weight along the existing edges of your forms, rather than actually defining new intersection lines.

When two forms intersect, the resulting intersection line is a new one that goes across those forms' surfaces to define exactly where they're connecting in space. Here's what I mean.

Lastly, your organic intersections improve between the first and the second. Both do a decent job of capturing how the forms interact with one another in 3D space, though the second one does a better job of establishing the illusion of gravity in how they slump and sag over one another. Also, the second one's cast shadows are far better - the first one has the shadows adhering a little too closely to the forms that cast it, rather than properly projecting onto the surface of the forms below.

So. I'm fairly close to marking this as complete, but I do want you to do one more page of form intersections. Take a little more time as you plan and prepare before each individual line (applying the ghosting method thoroughly of course, and one thing you may want to try out is lifting your pen when you hit the end point instead of slowing to a stop, as this can yield better, more confident results). And most importantly, take another swing at the intersections themselves - remember, at least part of these intersections are going to be new lines that cut across the faces of the forms, rather than following along the existing edges the whole way through.