Starting with your form intersections, very nice work. I'm pleased to see how mindful you were of the construction of each individual form, as well as how you considered the ways in which they would relate to one another in space.

Continuing onto your object constructions, as a whole the processes that you're applying are pretty solid. You're employing considerable subdivision to find more specific locations for both major elements in your constructions, as well as a lot of the smaller details. I'm particularly pleased with how you approached the buttons on your Cintiq - a lot of students at this stage, just getting used to all the subdivision and usually eager to avoid getting "lost in the linework" as you said, might eyeball and approximate those parts of their constructions. I'm very glad that you went in whole-hog and pinned each element down with greater precision. This fastidiousness and attention to detail will help you a great deal in Lesson 7, which is a lot like this - but on steroids.

I noticed that you did, at least sometimes, struggle with ellipses and curves - but assuming this submission is in chronological order, there was definitely improvement over the set in this regard. Looking at your weights, the unique issue of dealing with freehanded ellipses here was definitely challenging. While there's no good way to handle this (aside from an ellipse guide, which I'll talk about in a moment), the main thing I wanted to comment upon here was just the fact that you roughed the ellipses in more faintly, then traced back over them with a darker line.

As far as this course goes, that's an approach I want you to avoid. Every mark you put down, from beginning to end, should be committed - so that initial ellipse you draw, using the ghosting method and using your whole arm - should be the one that establishes the end of this given cylinder. Tracing back over the mark hesitantly will only imbue it with the wobbling and unevenness that will guarantee your form feels awkward and flat. Solidity comes from the simplicity of a confident execution, and while it's not going to be perfect (even at this stage - ellipses are difficult, and are going to demand a lot more mileage for any student at this lesson to get properly comfortable with), it will at least lean you closer to more solid results.

On the topic of ellipse guides, in this case you'd have needed some big ones - which only come in full sets, which are expensive. It's safe to say that it would not have been an option here. That said, I do want to mention that for the 25 wheel challenge, most students employ what's called a "master ellipse template". It's basically a single sheet that includes a variety of degrees, but limited to smaller sizes (usually an inch, an inch and a half). It's still well worth it (since it's way cheaper than a full set), and will help your work for the wheel challenge and your vehicles in lesson 7 focus on the more complex aspects of construction, rather than having you fret over freehanding ellipses. I strongly recommend it, even though it means your wheels will have to be smaller.

Anyway, going way down to your dog leash, I think you're handling your curves much better here. The hole in the bottom section is still hesitant and uneven - so that should have been drawn with confidence and commitment, drawing through the shape two full times before lifting your pen as mentioned way back in Lesson 1 - but still, this shows a good deal of improvement.

The last thing I wanted to point out is that you appear to have drawn your constructions using two separate pens - one to lay down the construction/scaffolding, and another to "commit" to your lines. This is probably why you ran into that issue with your ellipses. This is actually an approach that was specifically disallowed in the instructions, here, so make sure you read them more carefully in the future and that you avoid doing this in the future.

If you choose to work with a ballpoint pen, that is what you will be using for the entire drawing - and that is, for the purposes of this lesson and the one after it, something I'd recommend. Absolutely do not trace back over your drawing - tracing focuses more on how the lines sit on the flat page, rather than how they represent edges moving through 3D space.

Anyway, I'll go ahead and mark this lesson as complete.