Starting with your form intersections, your work here is looking great. At this stage we still believe it's normal for students to have some difficulty with this exercise - mainly in the areas involving curving surfaces - so we really only expect them to be more comfortable with intersections involving flat surfaces.

Arguably you're further along than that, showing a fair bit of comfort with intersections involving curved surfaces, although there are a handful of mistakes that I noticed suggesting that there's still room - as is expected - for continued growth. I've noted some corrections here and here - the main ones are where you inverted the curvature along the surface of a sphere, causing the intersection to dip into the sphere rather than running along its outside. It helps to always be cognizant of the specific nature of the surfaces involved in the intersection and how they flow through space, which this diagram seeks to explain a little further.

Continuing onto your object constructions, aside from that slight propensity to scratch out drawings you don't feel are going in the right direction - which is absolutely a habit you should be pushing yourself to break, as it does you no good and merely reinforces negative reactions to a very normal thing, you've done a fantastic job. I'm very pleased to see how thoroughly you're employing your orthographic plans, which lines up very nicely with the core focus of this lesson being on precision.

Precision is often conflated with accuracy, but they're actually two different things (at least insofar as I use the terms here). Where accuracy speaks to how close you were to executing the mark you intended to, precision actually has nothing to do with putting the mark down on the page. It's about the steps you take beforehand to declare those intentions.

So for example, if we look at the ghosting method, when going through the planning phase of a straight line, we can place a start/end point down. This increases the precision of our drawing, by declaring what we intend to do. From there the mark may miss those points, or it may nail them, it may overshoot, or whatever else - but prior to any of that, we have declared our intent, explaining our thought process, and in so doing, ensuring that we ourselves are acting on that clearly defined intent, rather than just putting marks down and then figuring things out as we go.

Here, you've built up your precision through the use of the subdivisions in your orthographic plan - giving yourself full opportunity to meaningfully study the proportions of the object in two dimensions, in as focused and distilled a manner as possible, before then applying them very effectively to your 3D construction, without having to actively make decisions while navigating the 3D space. That is precisely what I want to see, and you've done a great job with it.

I am also pleased to see cases like your mug's handle, which shows that you read, processed, and understood the point about starting our curves out with chains of straight edges/flat surfaces. Many students skip over that.

My only real complaint is where your work gets a touch messy - mainly in cases where you're trying to fill areas in with solid black (like the pencil sharpener and the cast shadows for the barrel). The issue is mainly that it seems you drifted away from the basic mechanics of markmaking from the course, and got very scratchy/haphazard for no good reason. If the issue there is a limitation on your tools (like if you only happen to have an extremely thick pen with which to fill things in, which you cannot reasonably control), given that these elements are somewhat superfluous from the focus of the exercise, it's better just to leave those elements out. Otherwise, take the time to execute them to what we both know to be the best of your current ability - something that was definitely not seen in the pencil sharpener.

Anyway, all in all, great work. I'll go ahead and mark this lesson as complete. What you're doing here so well - with the orthographics and all - is essentially what Lesson 7 is as well, but taken to an extreme. As long as you tackle it with the same kind of patience and avoid scribbling out your work (mistakes happen, but it's far more important to roll with them and figure out how to push forwards wherever possible), and you'll do great.