Hello! I'll give you a critique:

Organic forms with contour curves

Your lines are very confident and your accuracy is high, good job on that! I notice that you sometimes vary the size of a sausage, most likely because there's no room left on the paper. Try to avoid that by planning.

In my opinion some of your sausages have too many ellipses, especially on the first page. When in doubt, always come back to the core principle of the exercise - you're doing these to show that the sausages exist in 3D space, so your goal is to use as little contour lines as possible to achieve that.

Insect construction

Very solid constructions, I don't have much to say in this area, all of your insects look very much 3D. I suggest using less scratchy lines during the initial construction since some of that bleeds into the final image, even with added lineweight. I know these exercises are allowed to be messy, all I'm saying is I'm seeing areas where it could have easily been avoided, for example the cast shadows on the ground.

Also, I think you're adding way too many straight lines to the further legs. Same as my critique for your ellipses, you only need a few to convey the legs are in the distance. When you have this many, you create a focal point because hard edges attract attention.

When constructing the inside of a bug, it's always better to choose describing the form through contour lines rather than lines going parallel with the bug. Lines are flat by nature, but they are necessary in this course. It's better to communicate to the viewer the message "this line doesn't actually exist on the creature, it only describes it's form through contour" rather than "this line is part of the creature".

Texture

Texture isn't required here if you don't want to include it, but I'm kind of confused here since you have a bit of it on only some parts of the insects. Regardless, here are a few tips.

Firstly, you can completely ignore the colored patterns insects sometimes have on their bodies. I asked uncomfortable himself and he said this. You're only concerned with the cast shadows of the actual bumps and scratches if you decide to add texture.

Secondly, the surface texture on some of your insects feels rushed. You should place extra care in each and every line you draw, because each line is important. In areas like this one, I feel like you're on auto pilot mode which causes unpleasant repetition. You don't have to replicate every single hair and protrusion that happens on the image, a few is enough to convey the silhouette texture. A good way of checking how it looks is zooming out. Zooming out very very far. This allows you to asses if the added texture is enough. Since we're working on paper, you can stand across the room and look at your drawing, I think it should work the same haha.

Lastly, don't add the silhouette texture inside the insect if you're not drawing texture.