Your work here is honestly really well done. Starting with your form intersections, you're drawing the individual forms with a great deal of confidence, resulting in forms that feel solid, and with relationships between them that are really well defined. My only issue here is with the overuse of hatching - there is absolutely no need (nor benefit) to filling the intersections with hatching. Think of this sort of drawing as being a bunch of metal primitive forms that have been welded together. The intersection lines themselves serve as the "welds" we'd actually perceive - they're joints between the forms that would be visible if they were all connected. The additional hatching lines just serve to confuse the visual, and make things harder to perceive, rather than easier. To that end, I'm really glad you left them out of the next two pages, and as a result they become far easier to understand and make out.

Admittedly while your boxes aren't perfect (there are definitely divergences that should be convergences), they are still drawn confidently enough to make those issues a relatively minor issue.

Moving onto your object constructions, honestly your work is pretty fantastic. While the drawings following along with the various demos were admittedly a bit weak (and honestly seemed a little rushed), this is primarily in comparison to your own drawings, which received far more attention and care and pretty much all came out looking solid and precision-cut. You absolutely didn't take it easy on yourself either - basically every single object you tackled was incredibly complex, with a variety of geometric problems to solve and countless potential stumbling blocks.

The weakest of the bunch was probably the xbox controller - you struggled a great deal with the buttons and thumbsticks, and while I think I can see minor axes being positioned in the construction, it probably would have helped to have constructed the thumbsticks inside of boxes (since the boxes would have been easier to place relative to the rest of the structure). The gamecube controller was definitely much stronger in terms of the overall structure, and there was definitely improvement on the thumbsticks and buttons as well, the same suggestion still stands.

Despite these specific struggles, I think it is again a matter of the overall quality of your work being so strong here that it makes otherwise acceptable results (for this lesson, and this point in the course) stand out as not quite making the standard you've otherwise set for yourself.

Aside from that, there's really just one rather superficial suggestion I have for you as you move forwards: don't fill voids with black. In cases like the wiimote and the treasure chest, you filled certain spaces with solid black, and in doing so you effectively took any opportunity to understand what exists within that space off the table. While it is not at all abnormal to have parts of a drawing obscured by solid black shadows, the critical point is that what is being captured is a shadow. A shadow being cast by one form onto the surface of another, defining a relationship between them. It may drown out certain aspects of the construction, but it does so by introducing other information. In the case of the chest especially, only took information away, rather than providing any in return.

As a rule, make sure that every solid black shape you draw is always a cast shadow, and therefore you should be able to understand how that shadow shape relates to both the form casting it, and the surface upon which it is cast.

It's worth mentioning that in your violin drawing, the f-hole being filled in here is actually appropriate. That is for the simple reason that the shadows cast into the hollow of the instrument by the rest of the construction would be undoubtedly so large that they would fill in that space. It's still a cast shadow, but in this case we aren't expected to necessarily pin down the specific relationships between the forms casting it, the surface receiving it, etc. With the wiimote we have a similar situation, but due to the angle from which we're seeing that hole, we would ostensibly be able to see some of the inner surfaces out of shadow.

On the topic of the violin, this is obviously your strongest piece, simply for the sheer complexity you aimed to achieve, and the level of success you achieved with it. While admittedly some of the line work is a little shaky, the overall construction is still quite solid and very well constructed. You've done an excellent job of applying and mixing a number of concepts from the lesson, and while I suspect that the proportion of the violin's neck do seem a bit short, what's most important is that it still looks real, as though perhaps the violin-maker made a bit of a mistake.

All in all your work throughout this lesson is fantastic. I'll go ahead and mark this lesson as complete. Keep up the great work.