While I think there's definitely a lot of room for improvement on your organic forms with contour lines, your insect constructions are largely coming along really quite well.

The biggest issue with the organic forms exercise is that while you're definitely striving to keep your sausage forms simple, you do need to watch out for the tendency to stretch out those ends. We want them to be spherical, so any elongation will throw that off. I can definitely see you trying to think more about the degree of your ellipses however, and while that's better in some areas than others, overall it's moving in the right direction. Just be sure to continue practicing this exercise in your warmups.

Moving onto your insect constructions, I'm very pleased with how you're largely abiding quite closely to the concepts covered in the lesson. You're building your insects up from simple forms, paying close attention to how the forms you use relate to one another in 3D space, and how you can build them up to achieve greater complexity without ever jumping in with an overly complex form from the get-go.

While you generally had a good use of the sausage method, you did run into some more inconsistency with this spider, specifically with sausage forms that would get wider through their midsections, or have ends of different sizes. To this point, remember that we're really just interested in the sausage as being an underlying base structure, or an armature. We can always come back on top of it and build up further forms to add bulk where necessary, as shown here. When we introduce this kind of complexity too early, it risks undermining the illusion that we're dealing with a solid, three dimensional form, and that can definitely throw things off.

One other issue I'd like to point out is that in some cases, as shown here, instead of creating separate 3D forms to bridge the gaps between your primary masses, you'll extend the silhouette of those forms. The silhouette is a 2D shape - therefore extending it is a matter of manipulating your drawing in 2D space. This reinforces the idea that what the viewer is looking at exists only in two dimensions. We want to always work with 3D forms, as this will reinforce the idea that everything we're looking at is 3D. You can see this concept illustrated in this diagram. We can also see something similar with the scorpion's claw, where because the pincer portion isn't an independent, fully enclosed form with a clear relationship defined between it and the mass it connects to, it ends up reading as being more flat. You can see a demo about tackling claws like this here.

The last thing I want to mention is a minor point about the form shading you've added on this insect and this scorpion. As discussed back in Lesson 2, we aren't including any form shading as decoration in any of these drawings. Sometimes students will think, "okay time to add detail", and in their mind it'll be just about making the drawing pretty. Sometimes to do this they'll turn to basic form shading. That isn't what we're after here.

Instead, every mark we put down is focused on visual communication as the goal - in this case, adding actual texture to help communicate how the surface of the object actually feels to touch is what we want to be going for. In some cases form shading can afford us a place to sneak it in (where we transition from light to dark), but the goal is not simply to add form shading.

So! All in all, your work is looking pretty great, but you have a few things to keep in mind, and you definitely do need to continue practicing your organic forms with contour lines. I'll go ahead and mark this lesson as complete.