Jumping right in, it appears that you did not include the 2 pages of organic forms with contour curves with your submission. I will need to see those before I can mark this lesson as complete (I'm assuming you did them but just neglected to include them when gathering up your work), but for now I'll jump straight into the insect constructions.

As a whole you are doing a great job of holding to the premise of building up from simple to complex, and I can see a great deal of signs that you are thinking hard about how the different forms you're drawing exist in 3D space. This can however be pushed even farther, and I have some advice on how to adjust your approach to achieve that.

It comes down primarily to identifying the distinction between when we're thinking about our marks in 2D space (as though we're merely putting lines down on a flat page), and when we're thinking about the things we're drawing, and the things we've already drawn, as though they are complete, solid, three dimensional entities, engaging with one another in a 3D world. Because we're drawing on a flat piece of paper, we have a lot of freedom to make whatever marks we choose - it just so happens that the majority of those marks will contradict the illusion you're trying to create and remind the viewer that they're just looking at a series of lines on a flat piece of paper. In order to avoid this and stick only to the marks that reinforce the illusion we're creating, we can force ourselves to adhere to certain rules as we build up our constructions. Rules that respect the solidity of our construction.

For example - once you've put a form down on the page, do not attempt to alter its silhouette. Its silhouette is just a shape on the page which represents the form we're drawing, but its connection to that form is entirely based on its current shape. If you change that shape, you won't alter the form it represents - you'll just break the connection, leaving yourself with a flat shape. We can see this most easily in this example of what happens when we cut back into the silhouette of a form.

Here on one of your constructions I've highlighted in red where you've cut into the silhouettes of existing forms, and some of the spots where you'd either extended off their silhouettes with a partial shape, or added a one-off mark that effectively resulted in the same, in blue.

Instead, whenever we want to build upon our construction or change something, we can do so by introducing new 3D forms to the structure - forms with their own fully self-enclosed silhouettes - and by establishing how those forms either connect or relate to what's already present in our 3D scene. We can do this either by defining the intersection between them with contour lines (like in lesson 2's form intersections exercise), or by wrapping the silhouette of the new form around the existing structure as shown here.

This is all part of accepting that everything we draw is 3D, and therefore needs to be treated as such in order for the viewer to believe in that lie.

You can see this in practice in this beetle horn demo, as well as in this ant head demo. You can also see some good examples of this in the lobster and shrimp demos on the informal demos page. As I've been pushing this concept more recently, it hasn't been fully integrated into the lesson material yet (it will be when the overhaul reaches Lesson 4). Until then, those submitting for official critiques basically get a preview of what is to come.

Continuing forward, I noticed that you were generally making a conscious effort to apply the sausage method when constructing your legs - although there are some places where you'd stray a bit from the characteristics of simple sausages (which is itself not easy when they get so skinny), as well as some places where you'd forget to define that joint between the sausage segments with a contour line. As a whole though, I feel you're making a good effort to apply the method, and I hope you'll continue to do so as you tackle the next lesson's material, where it continues to be relevant.

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, in this ant leg, and even here in the context of a dog's leg.

And that about covers it! All in all, you're doing very well, but can definitely do even better by focusing on always ensuring every step adds a new 3D form, rather than just individual lines and flat shapes. You can continue to address this into the next lesson, so I'll go ahead and mark this one as complete.