Alrighty! Starting with your form intersections, these are looking really solid. Your linework is crisp and carefully planned out, and the relationships you've defined between the forms themselves are coming along reasonably well. They're not perfect - there are a few mistakes here and there some of which I've marked out here. Seems like there were some places where you just got a little bit turned around.

Looking over the submission itself, it's clear to me that you've learned a great deal over the course of this homework. As you worked through the demos, I can see a degree of uncertainty with the techniques and approaches, but as soon as you started applying them to your own chosen objects, you appeared to do so with a fair bit of confidence and success. There are only a few very minor concerns I have, and a couple observations.

It's not really worth looking at the demos - those were your runway, it's more useful to focus my time on the time you actually spent in the air. One thing that immediately jumps out at me is that while you certainly were not at all averse to subdividing your forms as much as you needed to put things down with a great deal of precision, in many cases you demonstrated a keen grasp of the relationships between your forms in 3D space, and the ability to estimate certain things and jump over a few logical gaps without undermining the solidity of your form. To put it simply - there were areas where most students would have opted to subdivide things further, where you were able to just approximate things and manage to pin those details down fairly well.

This is both good - in that it does demonstrate that you're quite capable at this, and bad - in that it could suggest that in the future you might find yourself in a situation where you probably should have relied on further, more tedious subdivision, but ended up overestimating yourself. Now, based on what I'm seeing here, I'm not at all worried - but I would say that when you hit lesson 7, the demands to subdivide things really far, to get extremely precise positioning for various details and features, will be pretty high. And I highly urge you to lean into them as much as possible. It'll take longer, but at the end of the day going through those steps is part of the core of this course - to appreciate just what you can achieve by pushing yourself as far as you will go, by putting your patience to the test. It's not something you'd do in your own drawings unless they really demanded it, but it's good to know the full scope of what you're able to achieve, given a lack of any time constraints, and a dead-set focus.

I don't want to give you the impression that I feel you were frivolous in your use of subdivision. You honestly used it where you ought to have in most cases. There were just a few things - for example the top knob thing on your lantern, which ought to have been constructed within its own box, ended up being slightly off-center and on a bit of a slant. There were also some other small details, like the curvature along the handle of the coffee grinder which could have been pinned down more specifically, but honestly I understand why you wouldn't want to do that with something quite so fluid in its curvature.

That said, I have had students go to the extreme, drawing things like model skulls (which admittedly should be outside of the scope of this lesson, but do a good job of showing just how far those techniques can be pushed).

Moving onto your cello, while the proportions were a little off, I'm not too worried about that. What I did want to point out was that one of the biggest challenges in this object is the fact that the neck of the cello is at a different orientation than the body of the instrument. This is the sort of thing we should be pinning down early on in our construction, creating an overall box for the body, and then another one for the neck, establishing the specific relationship between those forms and their slanting in space. It does look here as though the neck itself was drawn without this kind of overarching box, which threw off its orientation in space a little, relative to the body.

As it's great that you did those proportional studies, but I would definitely have done these on a separate page so the drawing itself could have been given as much space as it needed. Getting close to the edge like that can throw us off our game, causing us to make mistakes for no good reason.

Last of all, your microscope is frankly absolutely phenomenal. The construction itself is confident and bold, and the level of detail you explored is very impressive. While the construction itself isn't perfect - the box used for the base appears to diverge a little as we look farther back - I am not at all concerned about that. I think you built things up steadily and solidly, and the end result came out well. I suppose my only complaint is that the "tension" label doesn't quite stay on the surface of the form. Lettering is notoriously tricky, and I would have probably just left that off the drawing altogether. But no matter.

All in all you're doing a pretty great job with this, and you're showing a lot of strengths. I will happily go ahead and mark this lesson as complete.