Starting with your organic interesctions, these are spot on. You're doing a great job of drawing how the forms interact with one another in 3D space, how they slump under gravity, and so on.

Moving onto your animal constructions, there is a lot of good here. As a whole, you're showing a lot of good understanding of how to leverage solid forms in space, how to build up constructions steadily and how to work from simple to complex in order to uphold the solidity of your constructions from the beginning and avoiding choices that undermine that solidity. You're also showing a lot of use of the sausage method to lay out your legs, before building up further complexity on top of that. All of this is really serving you well to end up with detailed, complex constructions that feel real and tangible.

That said, the first thing I want to call to your attention is your heavy use of contour lines. Contour lines are great - they're an effective tool we can use to make a form feel three dimensional, and to take a flat shape and give it volume. That said, there is such thing as too much of a good thing - it's not uncommon for students to just pile on their contour lines, and this is usually a pretty clear sign that they're not necessarily thinking about what each contour line is meant to contribute to the construction.

Contour lines - the kind that sit along the surface of a single form, at least - exist to serve a specific purpose, and generally speaking the first one on a form is going to have the greatest impact. The second may help to reinforce the job of the first, and then very quickly you start to get into seriously diminishing returns where your third, fourth, etc. serve no real purpose at all.

It is incredibly important, before adding a mark to a drawing, to weigh precisely what it is meant to accomplish, how it is best going to do that job, and whether its task has already been handled by another mark. Long story short, you need to hold back. The vast majority of the contour lines you've added to your forms haven't been necessary. In fact, these kinds of contour lines are usually rendered somewhat moot by other more effective tools.

For example, the contour lines that define the relationship between forms (like the form intersection lines) are in fact vastly more effective, because of how they actually create a connection between forms, not only making an individual form feel a little more 3D, but making us understand both forms in relation to one another. This is why, in the middle of the sausage method diagram, I actually state that you should not be adding any more contour lines along the lengths of your sausage segments. The one placed at the joint is more than enough, when done correctly, to make the chain feel solid and 3D.

Then you've got the additional forms - they themselves define their relationship with another form in how their actual silhouette shows them wrapping around another structure. In this sense, it's like you took a contour line (which wraps around a form) and turned it into a 3D form of its own. As you can see in the part of the lesson about these additional masses, I actually don't show any contour lines along those forms because they don't need them.

In fact, not putting contour lines on your additional masses can actually help us, because it forces us to think more about how our silhouette is meant to wrap around. Many students fall into the trap of drawing arbitrary shapes (which appear flat on their own) and then piling on contour lines to make them 3D - but this neglects to actually define a clear relationship between the forms.

For the most part, you've avoided this, but there are some cases - like this donkey's belly where without the contour lines, the shape itself doesn't do a great job of suggesting that it's really wrapping around the torso.

As a whole though, I am quite pleased with how you handled your additional forms - there are ample cases where you've wrapped forms around the underlying structure, and that you've paid a lot of attention to how you're building things up. It's arguable that you just got a little too reliant on the contour lines, even though you didn't need them in most cases, because your constructions stand up well on their own.

As a bit of a side note, I do want to mention that in that donkey, the only weak parts are the hair along its neck and its tail, primarily because these broke away from the constructional principles you've otherwise applied so well, instead opting to create complex flat shapes (and in the case of the tail, add contour ellipses after the fact which didn't really accomplish much due to the complexity of the form).

For the hair along the neck, I would have constructed that as a flexible box running back (that area of hair is after all three dimensional), only adding a bit of fuzz along its top once the solid form was in place. You can see this shown in this informal donkey demonstration.

As a whole, I am still very happy with your results, and while your grasp of the material was strong throughout, I definitely saw nuanced improvements across the set - especially when it comes to the head constructions. From the donkey onward, you show an exceptionally good grasp of how to treat the head as a sort of 3D puzzle where all the pieces fit together, with muzzle, brow ridge, cheek bone, etc. all buttressing against a clearly defined eye socket.

All in all your work is very well done, though you do have some points to keep in mind as you move forwards. I'll go ahead and mark this lesson as complete. Keep up the good work.