Congrats on completing lesson 6! I'll do my best to give you useful feedback so that you can improve.

Starting with your form intersections, you've done reasonably well! The first thing that stands out to me is that you've drawn the intersection through the form and to the side we can't "see". This may be something you could consider doing when you've increased your understanding of how forms sit in 3D space but doing it now only flattens the forms and adds to the confusion. It helps to see these intersections as not between forms but between the surfaces of forms. Seeing them this way simplifies the exercise by giving you only 3 things to worry about. Flat-on-flat intersections, flat-on-round and round-on-round intersections. Flat on flat intersections only produce straight | lines. Flat on round intersections produce C curves (as seen on this diagram. Finally round on round intersections generally produce C and S curves, with S curves being the result of 2 C's. By simplifying the lines down to C, S and I the exercise is much simpler. For example, A box is made up exclusively of flat surfaces - six of them in fact - whereas a sphere consists of just one rounded surface. A cylinder and a cone on the other hand are made up of a combination, with the cylinder having two flat surfaces and one rounded surface between them, and a cone having one flat and one rounded. Thinking about the intersections in this manner - as a line that runs along these surfaces, effectively trying to find that one path that allows it to run along both surfaces simultaneously - helps a fair bit, but we can take that a step further by looking at how the intersection line changes as the forms in question are modified. This kind of algebraic thinking (2 F = |, F R = C, R R = C/S) can help see the intersections in a different perspective. Finally, before I move on you can take a look at this form intersection pack made by optimus on discord, or use paint 3D to make perfect intersections yourself and further your understanding.

Moving onto your object constructions, I can see that you've patiently and precisely built up the constructions using subdivision which is great! This lesson is the first point at which we really focus on the concept of precision in our constructions. Up until this point, going through Lessons 3-5, we're primarily working in a reactive fashion. We'll put down masses, and where the next masses go depends on how large or small we ended up drawing the previous ones. There's no specific right and wrong, just directions in which we're moving which impact just how closely we matched the reference. You can think of it as a manner of constructing that works from inside out. Conversely, what we're doing here works outside in - everything is determined ahead of time, and as we build out the various aspects of our construction, we either do so correctly based on our intentions, or we miss the mark.

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.

In our constructions here, we build up precision primarily through the use of the subdivisions. These allow us to meaningfully study the proportions of our intended object in two dimensions with an orthographic study, then apply those same proportions to the object in three dimensions. You've used subdivision very well on the object constructions themselves, but this can be taken further through the use of subdivison on orthographic plans. Which I can see you've done, but when I look closer at the plans I can see that they don't exactly tell you where the lines lie in 3D space. For example, taking a look at this side plan for the water bottle you seem to place lines without subdividing which makes them very hard to be replicated on the actual 3D construction. Through using subdivision like this we can precisely place where the edges of the water bottle lie. This draw over of uncomfortable's mouse demo does the same thing.

The reason we draw orthographic plans before drawing the actual 3D construction is so that we can make decisions of where everything will go before drawing the construction. By separating the decision making process and the thinking in 3D process we can more effectively focus on thinking in 3D while constructing the object. Note that I said "making decisions" - this is not about finding the "correct" proportion, but rather deciding which one you will be using. So if you had a drawer face with a handle on it, and that handle extended from the 19/50ths subdivision to the 31/50ths subdivision, that's... a lot to ask of a person. There's not a lot lost in rounding it to 2/5ths and 3/5ths, as long as that rounding doesn't accidentally eliminate some other important elements as a result.

Some final notes before I wrap up this critique

• It helps tremendously if you draw curves as a chain of straight lines first before drawing the actual curve because curves are imprecise and vague. This way we can build our construction more solidly first, then round them out later. you'll also notice that as a result of breaking the curves down into straighter chains, we end up with some clearer landmarks which we can then position at specific points along the length of a given dimension

• be careful with your filled areas of solid black. Reserve them only for cast shadows. From what I see you use it to mostly outline your objects OR as form shading to round out your objects, both of which should be avoided. Generally with cast shadows, they require us to design and create a new shape rather than filling in an existing shape. There are exceptions with this of course, for example your mug would definitely cast a shadow on the interior. This diagram could help with the distinction between the two.

Overall you've done a great job for this lesson and if you keep in mind what I've said here when you're doing lesson 7 you will have a much easier time with the lesson. If you have any questions or are unsure about anything don't hesitate to ask! Good luck!