Starting with your arrows, they're flowing very fluidly through space. You're also generally doing a good job of applying perspective to both their positive space (the width of the ribbon itself) and to the negative space (the distances between the zigzagging sections). When those gaps get especially small, however, don't be afraid to let them overlap. This will help you convey a stronger sense of depth in your scene.

Moving onto your organic forms, I'm noticing that you appear to be trying to stick to simple sausage forms, but there are some areas where you're not quite adhering to the characteristics outlined here. We can see a number of places where your sausages do not maintain a consistent width through their midsection, and areas where the ends are either of different sizes, stretched out instead of properly circular, or both. Definitely something to keep an eye on, as maintaining simple sausage forms will be important as we get into using these kinds of forms as base components in more complex constructions.

Your organic forms with contour curves are definitely better in this regard, although with some smaller deviations from the simple-sausage characteristics. Aside from this, your work on this exercise is well done. Your contour ellipses tend to be a little too consistent in their degrees, but you improved upon this in your contour curves as well and clearly demonstrated an understanding of how those contour lines' degrees actually correspond to the orientation of that cross-section in 3D space based on how you pointed them out as "too flat".

Moving onto your texture analyses, these are entirely in line with what the lesson and exercise talk about. You're clearly focusing on the use of clear shadow shapes rather than lines/outlines, and you're mindful of how to arrange them such that you achieve a gradual shift in density from left to right. Your observation and attention to detail is pretty decent - there's definitely more room for refinement, to pick up on more specific little details and really digging into all that's there in your references, but as it stands you're doing a great job. I don't get the impression that anything is overly simplified or cartoony, so you're headed in the right direction.

You continue to improve upon this throughout your dissections, although I am noticing more of a tendency here to rely on outlines when dealing with certain kinds of textures. With textures that have more discrete, individual textural forms - like feathers, scales, stones, etc. you fall back to outlining each and every one of these forms instead of just relying on drawing the shadows they cast on their surroundings. I understand that it's difficult, that it forces you to have to really focus on a single form and the surfaces immediately surrounding it, and that it doesn't allow you to really pin down where everything is ahead of time - but really force yourself to work with shadow shapes only with absolutely no outlines. This will allow you to continue controlling the level of density in your textures. You can read up on this issue here.

Moving onto your form intersections, you're making good progress in this area. In many places you're constructing your forms such that they feel reasonably cohesive and consistent with one another, although you do have a tendency to apply more dramatic foreshortening to some of your boxes, which can throw off the sense of scale across the whole set. Try and keep your boxes more shallow - converging very slowly towards a far off vanishing point, rather than more rapidly. Also, while you used minor axes when constructing your cones, it seems you neglected to do so when drawing cylinders. This is demonstrated in the diagram on this step of the instructions.

You've got a great start on your intersections. Ultimately with this exercise, we're just introducing students to the idea of defining the relationships between their forms. This grasp of spatial relationships is something at the very core of Drawabox as a whole, and so it's something we're going to explore a lot throughout the course. Right now we don't expect students to have any prior experience or any comfort with the challenges, so there's going to be difficulty. By planting the seed and exposing you to the concepts here, you'll be better equipped as we continue to dig into them as we continue on.

Lastly, your organic intersections are looking great. You've clearly defined how these forms interact with one another in 3D space, rather than as shapes piled onto one another in two dimensions, and have established a strong illusion of gravity in how they slump and sag over one another.

All in all, there are a couple things to keep an eye on but for the most part you're doing very well. I'll go ahead and mark this lesson as complete.