Starting with your organic intersections, these are for the most part moving in the right direction, but there are a few things I really want to stress. Firstly, avoid the whole "one big mothership form and a bunch of teeny weenies" thing. It just makes the exercise a lot harder than it needs to be, whereas keeping them more similar in size will help you pile them up more easily. Secondly, really do focus on the idea that you're creating a physically plausible pile of sausage forms. Don't glue forms onto the side - always abide by the rules of gravity.

Moving onto your animal constructions, your work here is coming along quite well. There are a few things I want to share with you to help you keep moving in the right direction, but I am pleased with how you're thinking through the way in which each animal is built up from simple forms, and through the manner in which those forms are combined with one another.

The first thing that stands out is simply that you're packing a lot of drawings into each page, and while it's certainly an admirable thing, it does also mean that you're ending up with a lot less space for each individual drawing. Giving yourself less room can make it harder for your brain to work through spatial problems, and can also make it harder to engage your whole arm while drawing. Always focus first on having that first drawing take as much room as it needs on the page, then once it's done, you can assess whether the leftover space can accommodate another drawing. If it can, then great - go ahead and add another. If it can't, it's okay to just have one drawing on a page - as long as you're making good use of that space. I definitely feel that with more space to work through these drawings (in some cases there was more space, but there were large gaps left between the drawings), you'd have benefitted more from each exercise.

The second point I wanted to call out is simply that you have a tendency to use a lot of contour lines, and many of them aren't actually contributing much. Contour lines - specifically those that sit on the surface of a single form, as we were introduced to in the organic forms with contour lines exercise from lesson 2, suffer from diminishing returns. Piling them onto a form without thinking about it can result in a lot of extra lines with minimal benefit. While it's an effective way of first introducing the concept of a contour line, it's important to keep in mind that they suffer from diminishing returns. The first contour line may have a lot of impact in helping to describe how a surface deforms through space, but the second will have less impact, and the third even less. Furthermore, there are situations where students will, knowing that they're going to pile on a ton of contour lines, put less effort into each individual one, leading to a situation where they're prioritizing quantity over quality (like the belly of your caiman).

The ghosting method itself has three distinct phases, and the first one - the "planning" step - is what helps us to avoid overusing this kind of technique. It requires us to determine what the purpose of a given mark is meant to be, how it's meant to accomplish that goal in the manner in which it's drawn, and whether another mark is already doing the same job.

Now, all contour lines are not the same - the type we introduced in the form intersections exercise, which define the relationship between multiple forms are much more effective, and can't actually be piled on in this manner (since there's only one intersection to be defined between two given forms). They have a lot more impact, and just help everything feel more solid without being wasteful.

Before I get into the last suggestion, I do want to remark that I think overall you're making a lot of great use of the additional masses, and while the overuse of contour lines is somewhat diminishing your progress there (students sometimes feel like they can "fix" imperfect additional masses by adding contour lines, when in fact only paying more attention to the design of that mass's silhouette will do the trick), I do think you're still making excellent progress here. You definitely think quite a bit about how those new masses wrap around the existing structure, and with continued practice I can see you getting even better at this.

The last thing I wanted to call out has to do with head construction. Looking at your approach, right now you still have a tendency to have a lot of eye sockets/eyes that float somewhat loosely on the head, which suggests to me that you haven't gone through this explanation of how to approach head construction from the informal demos page. While it is relegated to the informal demos page, that is really where the more recent stuff goes, until it can be integrated into the lesson proper - and this one in particular is linked off from the tiger head demo page, right at the top, because it's very important. It goes over how the head itself should be constructed in a way that wedges all of its elements together - the eye socket with the muzzle, with the browridge/forehead, etc. The specific eye socket shape, of an upturned pentagon, especially helps with this, but the mentality of all the pieces fitting together like a three dimensional puzzle is very helpful in maintaining a solid structure. So, I recommend you go through that explanation and try to apply the approach to your animal constructions in the future.

Anyway, all in all, you're making good progress, and I feel the points I've raised here should help continue pushing you forward. I'll go ahead and mark this lesson as complete, and leave you to apply those points on your own.