Starting with your organic intersections, nice work! One thing to keep in mind however is that this exercise focuses on creating a believable, three dimensional pile of forms all interacting with one another in space, under the force of gravity. Try to avoid adding forms that defy the laws of gravity - basically anything that gives the impression that in the next moment, the pile's going to change/move. So for example, this one at the top here, and this arrangement here.

Continuing onto your animal constructions, there's a lot of good stuff here, and I can see that you've made an effort to use a lot of the techniques, tools, and demonstrations from the lesson when working through these constructions. There are some points I can suggest to help you improve and generally make better use of these drawing exercises, but as a whole I do think you're moving in the right direction here.

There are a few things that stand out to me most:

• You're holding very firmly to the idea that these drawings are exercises, and that the focus is on how you build up your constructions through the addition of new forms, establishing how they relate to the existing structure - either with a contour line in the case of a form penetrating another (to define the intersection line between them), or through the design of the new form's silhouette, to establish how it actually wraps around the existing structure. This second one can definitely be improved, and we'll talk about this further, but overall I'm very pleased with how much you've focused on using the technique.

• Your head construction approaches shows a strong grasp of 3D space, and how construction is all about building up a puzzle, one piece at a time. You're focusing a great deal on establishing those spatial relationships, and don't fall into the temptation to draw what you see, which tends to result in drawing way more complex shapes that don't feel solidly 3D.

So the first area in which your approaches here can be improved is to look at the specific way in which we can think about designing those additional masses' silhouettes. You're already doing this fairly well, but there are some key points that will help take it further.

One thing that helps with the shape here is to think about how the mass would behave when existing first in the void of empty space, on its own. It all comes down to the silhouette of the mass - here, with nothing else to touch it, our mass would exist like a soft ball of meat or clay, made up only of outward curves. A simple circle for a silhouette.

Then, as it presses against an existing structure, the silhouette starts to get more complex. It forms inward curves wherever it makes contact, responding directly to the forms that are present. The silhouette is never random, of course - always changing in response to clear, defined structure. You can see this demonstrated in this diagram.

There are a lot of elements of this you're already using (as I mentioned), but there are two key issues:

• You have a tendency to put corners (a form of complexity) in areas where they don't actually press up against anything else in order to form that complexity. The strongest example I could find of this was ion this bear - although honestly I think you improved in your use of additional masses over the set, so we're going to look at this giraffe instead where the issue isn't quite so clear cut. So for example, we've got these sharp corners here on the neck. Instead, note here how I would design that silhouette. And then from there you can steadily build up more structure as shown here - if we have a specific mass we're pressing up against, we can use inward curves and sharp corners, but unless that mass has been defined already, then we have to use the more gradual, smoother corners.

• When building upon your animals' legs, you're more prone to actively avoiding inward curves and sharp corners altogether, resulting in a lot of blobby shapes that don't quite "grip" the sausage structure underneath. Again this is most prominent in that bear I linked in the previous point, but we can also see it to a lesser degree in your elephant's legs as well.

The only other thing I wanted to call out is that you do have a tendency to slap down some contour lines that don't strictly serve a purpose. You don't do this especially often, but it does come up here and there - for example, here on this shark's underbelly. I think these are likely situations where the silhouette of those additional masses (again seemingly avoiding sharp corners and inward curves) wasn't quite right, so it felt flat, and you tried addressing it with contour lines. In this case I would still avoid the contour lines for two reasons:

• They don't actually help establish how those masses relate to the existing structure, so while they do a little to make it feel more 3D in isolation, it doesn't actually solve the problem at hand.

• They do however train our brain to think that when we don't design the silhouette correctly, we can still "fix" the issue. This encourages us to spend less effort/attention on the silhouette design in turn, which merely exacerbates those issues.

I am largely quite pleased to see that you appear to have leveraged major elements from the informal head construction demo. While you don't follow it all the way each time (for example, you might neglect to define the forehead here and there), you are holding to its core principles, and to great effect. I would still encourage you to try to apply that particular approach when doing constructional drawing exercises using animals in the future, as closely as you can. Sometimes it seems like it's not a good fit for certain heads, but with a bit of finagling it can still apply pretty well. To demonstrate this for another student, I found the most banana-headed rhinoceros I could, and threw together this demo.

I also wanted to give you this basic breakdown of how I'd approach constructing an elephant. Not because you need it, but because I'd made it recently and I feel like it wouldn't hurt to see how I might approach constructions similar to those you'd done yourself.

All in all there are points to work on, but I'm pleased with your progress, and I feel you should be good to address these on your own. So, I'll go ahead and mark this lesson as complete.

Edit: I just remembered that I did not answer your question about fur - although I'm not sure I fully understand your question. Could you provide an example?