Alrighty - so there's a lot of great progress here, and many of these have come out quite well. But there's also a few issues I want to point out to help keep you on the right track.

Starting with your organic forms with contour lines, it seems that in many of these you are indeed trying to stick to the characteristics of simple sausage forms as mentioned in the instructions, but there are definitely some deviations. Here and there you end up with some with one end much larger than the other, or sharp turns that result in a much stiffer form. Remember to draw these marks from your shoulder to avoid the particularly sudden shifts in trajectory that might occur when your elbow's radius ends up not being quite enough for the stroke.

Also, you should definitely still be overshooting your curves rather than having them stop right at the edge of the silhouette, in order to ensure that the trajectory of those curves hooks back around and gives a strong impression that these marks are actually running along the surface of the 3D form.

Continuing onto your insect constructions, the first point I want to raise is just the importance of drawing things big. As big as they need. Sometimes we get caught up in wanting to pack as much as we can into a given page, and as a result we end up drawing things smaller, giving them less space than they really need. This in turn limits our brain's capacity for spatial reasoning and also makes it harder to engage our whole arm while drawing (making it more likely that we're going to slip back to using our elbows and wrists). Instead of trying to preplan how many drawings are going to go into a single page, give each drawing as much room as it needs, and once you've got the first one in there, assess whether there's enough space for another. If there is, add it. If there isn't, it's okay just to leave it as is and move on.

Another thing I noticed was that your drawings got noticeably weaker when you started delving more and more into detail and texture, and when you did so, you appeared to be much more focused on making your drawings look pretty and developed, rather than actually focusing on texture.

What we're doing in this course can be broken into two distinct sections - construction and texture - and they both focus on the same concept. With construction we're communicating to the viewer what they need to know to understand how they might manipulate this object with their hands, were it in front of them. With texture, we're communicating to the viewer what they need to know to understand what it'd feel like to run their fingers over the object's various surfaces. Both of these focus on communicating three dimensional information. Both sections have specific jobs to accomplish, and none of it has to do with making the drawing look nice.

If you remember back in Lesson 2, I mention that we don't get into any shading/rendering in this course, and it should not be used in these drawings. Instead, focus only on what you're trying to communicate, and only add as much as is required to meet that goal - don't overdo it.

As a side note, these drawings should all be done with a pen of the same thickness - ideally 0.5mm. Don't reach for a thicker pen to add line weight or anything like that. The only situation where you can reach for a thicker pen, or a brush pen, is to fill in shadow shapes you've already outlined and designed.

Next, take a look at these. The constructional method is built upon the idea of working from simple to complex. We build up complexity not by drawing forms with more complex silhouettes, but rather by building up more simple forms, and defining how they connect, wrap around, or otherwise relate to the existing structure.

A very common mistake that students will make is to manipulate the silhouette of a form they've already drawn - either by extending/redrawing it to include little spikes like you did on the left there, or by cutting back across the silhouette of a form. I'm not seeing any of the second one in your case, but in case you're not sure what I mean, you can check out these notes.

As for building up features constructionally, here's a demonstration of building up a beetle's horn. Notice how each piece that is added is in itself a full, complete silhouette, and the silhouettes either wrap around the existing structure, or some other kind of relationships is defined with what already exists in the world. You need to imagine it as though you are physically adding new forms, and that you're connecting them to one another. Not just drawing lines on a page.

Now, I did want to mention that these drawings are by and large far better than the others. Not only do they demonstrate a far greater attention to the underlying forms and structures, but they're also making better use of texture (at least the top right one, the others are still a little iffy, more decoration than communication). You actually added the red pretty well, but that is outside of the scope of this course - we ought ot be treating all our constructions here as though they're covered in the same white colour, not capturing any colour information (including areas that are black). Filled shapes should be reserved only for cast shadows.

The last thing I noticed that you seem to have employed a lot of different strategies for capturing the legs of your insects. It's not uncommon for students to be aware of the sausage method as introduced here, but to decide that the legs they're looking at don't actually seem to look like a chain of sausages, so they use some other strategy. The key to keep in mind here is that the sausage method is not about capturing the legs precisely as they are - it is about laying in a base structure or armature that captures both the solidity and the gestural flow of a limb in equal measure, where the majority of other techniques lean too far to one side, either looking solid and stiff or gestural but flat. Once in place, we can then build on top of this base structure with more additional forms as shown here, here, this ant leg, and even here in the context of a dog's leg (because this technique is still to be used throughout the next lesson as well). Just make sure you start out with the sausages, precisely as the steps are laid out in that diagram - don't throw the technique out just because it doesn't immediately look like what you're trying to construct.

So, with that, I do think you're doing well enough to move on - just make sure you get the whole detail/decoration thing sorted out, and that you adhere more closely to proper construction as you move into the next lesson.