Starting with your organic intersections, there are a few things you should keep in mind:

• Firstly, remember that the forms are resting on a ground plane, so it should also be receiving cast shadows.

• It's important that you keep track of where your light source is, so you know which direction those shadows will be cast. You don't want to end up in a situation where you're casting shadows both to the right and to the left, for instance.

• Keep working on sticking to 'simple' sausages (as explained here) to focus on making those forms feel as solid as possible. The simpler a form is, the easier it is to make it feel solid.

Continuing onto your animal constructions, there's a lot of things to talk about - there's a lot of things you're doing quite well, as well as a number of issues that I think we can address to yield considerable growth and improvement.

So the first issue I'm noticing across the board, is just that you're seeeeriously overusing contour lines. Normally when I see students covering their constructions with tons of contour lines (specifically the kind introduced in the organic forms with contour lines exercise, where the contour lines sit on the surface of a single form), it suggests that the student in question isn't necessarily thinking through what exactly each mark is meant to contribute to their construction.

Contour lines are a very useful tool, but on a case by case basis they can be incredibly helpful, or contribute very little. It's necessary to weigh just what exactly it is you're looking to achieve with the addition of any mark - that's what we do during the planning phase of the ghosting method, after all - and how we can draw it to get the most out of it. When you start piling contour lines onto a structure, you're quickly going to find that they suffer from diminishing returns. The first one may help make the form feel more three dimensional, the second less so, and the third may have no impact whatsoever.

There's also something to be said about the different kinds of contour lines. These, as mentioned before, were introduced with the organic forms with contour lines, but the form intersections exercise from lesson 2 also introduces us to a kind of contour line - one that defines the intersection or relationship between forms in 3D space. These are incredibly useful. Any opportunity you have to define that relationship between forms is one you should take - it's why we stress its use in the sausage method, as shown in the middle of this diagram.

Constructional drawing as an exercise really does focus on the idea of establishing how different forms exist in space, and how they relate to one another. Alongside these form intersection contour lines, there's also a lot to be said about what is first introduced with the organic intersections exercise - how we can establish the relationship between forms that wrap around one another, rather than intersecting.

I noticed that your overuse of contour lines definitely came into play when adding the additional masses to your structures. For example, looking at the masses you added on top of these birds' heads. You slapped a form on there, then covered them with contour lines to make them feel more three dimensional. This worked okay on the dove, because your form's mass actually wrapped noticeably along the curvature of the cranial ball, but on the kingfisher the bottom edge of the additional mass appeared to be much straighter, not quite taking that curvature into consideration.

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.

Moving onto how you approach your animals' head construction, I think it's moving in the right direction, but there are a few factors that are holding it back:

• Most of all, there's clear signs that you're not necessarily investing as much time into the head construction. As explained here, head construction revolves very much around how you design your eyesockets, how you actually cut them into that cranial ball. In your work, the signs I'm seeing suggest that you may have underestimated their importance, and constructed them without as much care as you could have - perhaps choosing to invest that time elsewhere. At the end of the day, of course, every part of a given construction should be given as much time as is required to execute it to the best of your ability - but in practice, we inevitably end up choosing which battles to fight, and which hills aren't worth dying on.

• Looking at that head construction demo I linked, the shape of the eye socket is important - note how they're pentagons with a point facing downwards. This allows for a nice little wedge in which we can fit the muzzle, as well as a flat top across which we can lay the brow ridge. This is a pattern you'll find useful in most head constructions. I noticed that based on how you were constructing your animal heads, you may not have seen this demo, or studied it extensively - I hope to expand this process to be the basis of new video material on this topic, but until I'm able to set aside time to produce that material, I did include a little blurb at the top of the main tiger head demo, informing students that they should pay special attention to this informal demo.

• In this kitten/cat drawing, I noticed that the shapes you used didn't correspond to eye sockets - it seemed here you fell back into drawing the eyes themselves. Always work from the eye sockets, then drop in a sphere for the eye ball, and finally wrap masses around that eyeball to create the lids. It seems here you may have jumped too readily into drawing things as you saw them, rather than building your way up.

The last point I want to raise for now - the critique does appear to be getting rather lengthy - is simply that you're not really employing the sausage method all that consistently when constructing your animals' legs. This is something I called out in my critique of your lesson 4 work, so I'm not going to dwell too heavily on it here - you can go back and read it there to refresh your memory.

That said, you also were very loose in terms of whether you'd build things up using complete, enclosed, 3D forms, or if you'd add individual lines or shapes to your drawing that were entirely two dimensional. For example, here on your elephant's underbelly we can see where you just added a line to capture a feature you saw - rather than building up as its own solid mass and considering how to define the relationship between it and the existing structure.

This is something I actually talk about most often in lesson 4, but based on what you'd submitted there it didn't seem to be an issue at the time. Here's the explanation I usually give on the topic:

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.

Instead, whenever we want to build upon our construction or change something, we can do so by introducing new 3D forms to the structure, 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.

You can see this in practice in this beetle horn demo, as well as in this ant head demo.

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. The more we jump through the hoops of actually viewing our construction and the parts we add to it, the more likely our result is to convince others of its three dimensionality. So, refrain from adding shapes or individual lines to alter the drawing - build upon the solid, 3D construction instead, using yet more solid, 3D forms.

I'm going to assign some revisions below, but when doing them, I want you to hold to one specific restriction: do not add any contour lines that sit along the surface of a single form. You can still use those that define the intersection between forms (like in the sausage method, whose specific requirements you'll have to review), and you are encouraged to do so. It's just the kind that were introduced with the organic forms with contour lines that I'd like you to leave out.