Hello Esteban90, I'll be the teaching assistant handling your lesson 5 critique.

Starting with your organic intersections, your lines appear smooth and confident and you're doing a good job of drawing your forms slumping and sagging over one another with a shared sense of gravity.

When practising this exercise in future, you will get more out of it if you draw through your forms. Drawing each form in its entirety will push you into thinking through how the whole form exists in 3D space.

You're projecting your shadows boldly, and exploring some rather challenging lighting angles with a fair bit of success, nicely done.

Moving on to your animal constructions your work is honestly very well done. Your constructions feel 3D, like sculptures I could reach out and touch, and your ability to push the foreshortening in your hybrid construction shows you have a very strong understanding of the 3D space you're creating.

I did spot a couple of hiccups, and have a few pieces of advice to offer to help you take these further, so let's get to it.

So, while you're mostly doing a great job of taking actions on your constructions in 3D by drawing complete new forms when you want to build or change something, there are a few 2D actions popping up here and there. Here is an example on one of your birds, where the tail has been extended off the form of the body as a flat partial shape, rather than a complete fully enclosed form. I haven't marked this as an issue on the wings, as we can treat paper-thin structures like feathers and fish fins like forms that are already flat. For the voluminous form of the bird's body, we need to add a complete form with its own fully enclosed silhouette to reinforce the illusion that the ellipse is a 3D ball, not a flat shape.

There are a couple of spots where it looks like you've cut back inside the silhouette of forms you have already drawn, such as the areas marked in red on this crocodile. I'm not hugely concerned, because it looks like you've attempted to apply these cuts in 3D, being aware of how the boxy form sits in 3D space. While it's entirely possible to do this correctly in 3D space, I'm advising students not to work subtractively at all when building up organic structures within this course, just because students tend to be prone to doing it wrong without realising, and then reinforcing 2D thinking instead. Sticking to working additively in 3D space will on the other hand be a lot harder to do wrong (as long as you're somewhat mindful of what you're doing), and will ultimately reinforce that 3D thinking and eventually help you subtract more effectively as well.

On the same image I marked in blue where the upper jaw had been extended in the same manner we would approach adding edge detail to a leaf, which starts to flatten out the boxy form of the muzzle.

I'm happy to see you making use of additional masses throughout your pages, and you usually wrap these masses around the underlying structures, with attention to how these forms actually exist in 3D space.

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.

So, your masses are working pretty well, but do make sure you give each one its own complete silhouette. If we take a look at this crocodile I've marked in blue where you'd attempted to draw an additional mass on the neck area, but where it reaches the head it just stops existing. This is a partial shape. Make sure to draw through your forms and complete them even if they pass behind something else. Here is how I might go about adding bulk to the neck. I've broken this addition into two forms, so each one can have a specific relationship with the underlying structures defined, rather than trying to fully enclose an existing form, following the same concept illustrated in this diagram.

On this horse I've made a few more edits to some of your additional masses. All your masses were already 3D, good work. What I've done here is wrap the masses on the belly and the rump more boldly around the underlying structures, in pulling the masses around the sides of the body more, we give them a stronger grip.

On the leg I've taken some places where you'd encapsulated the joints will ball-like forms, and wrapped additional masses around them instead. In pushing these masses against each other and wrapping them around, we have more control over the final result of the leg forms, and can build something that feels more organic. The more interlocked they are, the more spatial relationships we define between the masses, the more solid and grounded everything appears.

You are off to a good start with exploring the use of additional masses to build on your leg structures, but this can be pushed farther. A lot of these focus primarily on forms that actually impact the silhouette of the overall leg, but there's value in exploring the forms that exist "internally" within that silhouette - like the missing puzzle piece that helps to further ground and define the ones that create the bumps along the silhouette's edge. Here is an example of what I mean, I've blocked out masses along the leg there, and included the one fitting in between them all, even though it doesn't influence the silhouette. This way of thinking - about the inside of your structures, and fleshing out information that isn't just noticeable from one angle, but really exploring the construction in its entirety, will help you yet further push the value of these constructional exercises and puzzles.

I can see you experimented with a few strategies for constructing feet, and some of these are 3D. Sometimes you'll construct a 3D foot, then add toes as one-off lines, such as seen in this dog. I think you may find it helpful to take a look at these notes on foot construction which show how we can use a boxy form to introduce structure to the foot, and use more smaller boxy forms for the toes. This will enable you to avoid working with single lines or flat partial shapes.

The last thing I wanted to talk about is head construction. Lesson 5 has a lot of different strategies for constructing heads, between the various demos. Given how the course has developed, and how Uncomfortable is finding new, more effective ways for students to tackle certain problems. So not all the approaches shown are equal, but they do have their uses. I can see from your discussion post that you are aware that the current approach that is the most generally useful, as well as the most meaningful in terms of these drawings all being exercises in spatial reasoning, is what you'll find here in this informal head demo.

There are a few key points to this approach:

1- The specific shape of the eye sockets - the specific pentagonal shape allows for a nice wedge in which the muzzle can fit in between the sockets, as well as a flat edge across which we can lay the forehead area.

2- This approach focuses heavily on everything fitting together - no arbitrary gaps or floating elements. This allows us to ensure all of the different pieces feel grounded against one another, like a three dimensional puzzle.

3- We have to be mindful of how the marks we make are cuts along the curving surface of the cranial ball - working in individual strokes like this (rather than, say, drawing the eye socket with an ellipse) helps a lot in reinforcing this idea of engaging with a 3D structure.

You've done a great job of employing the major points from the informal head demo to the majority of your head constructions. Just keep in mind the point I made earlier in this critique about how altering existing forms with single lines will undermine the 3D illusion.

So! Overall you've done a cracking good job here, I'll go ahead and mark this lesson as complete.