Jumping right in with your form intersections, you're off to a great start. Your intersections themselves look good - you've got a wide variety of intersections at play, and each of them demonstrate clear consideration to how the individual surfaces are intersecting, and how those pieces are stitched together at each transitional corner between the surfaces. From the flat-on-flat, flat-on-round, and round-on-round, everything is looking good. As to your cylinders in boxes, you're generally doing well here too, save for one important point to keep in mind going forwards - we need your ellipses to fit snugly within their containing planes, in order to identify the correct contact points, and ensure that the ellipse as a whole is describing the plane in question properly (and so having direct relationships with the box's proportions). Having your ellipses floating more loosely within them does undermine the exercise a fair bit, resulting in weaker relationships and thus more diluted feedback in the analysis. I can see that you were using your ellipse guides here - given that they didn't fit correctly, the right move there would be just to freehand them to the best of your ability, given how big those gaps between the ellipse and the plane's edges are.

Continuing forward, your initial misconception with the form intersection vehicles is a common one, and not really a huge deal - but I am very pleased to see that you corrected it with the third and fourth. The purpose of the exercise is really just to remind students that what they're working on is still made up of simple forms, even though we're working primarily from an outside-in, precision-focused approach.

That said, as a whole you've done a great job with your vehicle constructions. I do have a few points to call to your attention, but they're largely superficial. When it comes to the approach you've used to build up each structure, I can see a great deal of patience and care, along with clear adherence to the core principles behind how we break everything up, working from simple to complex, and making decisions ahead of time so as to help you focus on just constructing your forms as you execute each individual mark.

So, structurally, your work is great. Where you run into some issues really just comes down to how you're approaching your detail - focusing on more general decoration of the drawing itself, doing what you can to make it more visually pleasing - rather than adhering to the principles from the course. This actually relates quite a bit to what I'd discussed in the feedback on your 25 wheel challenge - it pertains to how you're using those filled areas of solid black, and the fact that you aren't strictly limiting yourself to using those filled black areas for cast shadows only. You tend to jump between filling void spaces in, filling side planes in (which is more akin to form shading, which as discussed here in Lesson 2 is not something we're meant to include in our drawings for this course), and in cases like this otherwise fantastic VW beetle, putting some more generally arbitrary marks down, without considering the textural forms that are present to create those shadow shapes.

It comes down to the fact that you're focusing on decoration, which itself is not really a clear goal (there's no specific point at which we've added enough decoration, it's always arbitrary/subjective). What we're doing in this course can be broken into two distinct sections - construction and texture - and they both focus on the same concept. With construction we're communicating to the viewer what they need to know to understand how they might manipulate this object with their hands, were it in front of them. With texture, we're communicating to the viewer what they need to know to understand what it'd feel like to run their fingers over the object's various surfaces. Both of these focus on communicating three dimensional information. Both sections have specific jobs to accomplish, and none of it has to do with making the drawing look nice.

Instead of focusing on decoration, what we draw here comes down to what is actually physically present in our construction, just on a smaller scale. As discussed back in Lesson 2's texture section, we focus on each individual textural form, focusing on them one at a time and using the information present in the reference image to help identify and understand how every such textural form sits in 3D space, and how it relates within that space to its neighbours. Once we understand how the textural form sits in the world, we then design the appropriate shadow shape that it would cast on its surroundings. The shadow shape is important, because it's that specific shape which helps define the relationship between the form casting it, and the surface receiving it.

As a result of this approach, you'll find yourself thinking less about excuses to add more ink, and instead you'll be working in the opposite - trying to get the information across while putting as little ink down as is strictly needed, and using those implicit markmaking techniques from Lesson 2 to help you with that.

While I recommend you review the texture section in general, start with these reminders.

There is one "exception" I do want to quickly note however - though the way I explain it, it's not really an exception to the rule. It's the interiors - if we look at that same VW Beetle, you've filled the interior with solid black, and this is correct. A basic rule of thumb I'll generally use is that "if you catch yourself filling in an existing shape in your drawing, rather than designing a new one, you should stop and reflect on whether or not you're drawing a cast shadow, or just adding something more like form shading". In this case, you are indeed filling in a shape - but because it's on the inside of the car, we can basically view it as though the outer shell is casting shadows onto the interior, and in having that shape clearly designed to suggest the cut-outs for other windows and such, it still does work as a cast shadow, rather than formshading. Of course, we're not considering the fact that light would come in through the windows to light up sections of the interior - but regardless, the overall shape language is much clearer this way. So exception or mental gymanistics - whichever it is, that part is perfectly fine.

And that about covers it! As a whole you've still done a fantastic job. It's very valuable to consider how we deal with texture to be an extension of the same spatial reasoning concerns we deal with throughout construction, but all in all you are more than equipped to address that in your own practice. So, I'll go ahead and mark this lesson, and the course with it, as complete.

As to your question about the other course, I don't really have a ton of advice to offer, aside from doing your best to apply the instructions your instructor imparts to the letter. There may be situations where what they recommend conflicts with what you've learned here, and that's perfectly okay. Each course will basically exist in its own ecosystem. They have expectations for what you should know, and goals on what they're gonna try and help you develop, but the approaches they use can be very similar, or wildly different. Frankly, situations where they're similar are where we run into issues, because we may feel more inclined to follow another course's approach. But this would be incorrect, as you can't really know what reasoning the instructor has for having you do things a certain way.

One example of this is that while here we stress the need to draw through all of our freehanded ellipses two full times before lifting your pen. The course you're about to take may specifically require you to draw all your ellipses in one go. Each instruction exists within the context of its own course - so just as it'd be wrong to say, "instructor so and so told me to draw it in one turn of the ellipse" and ignore my instructions of drawing through your ellipses when doing drawabox work, it'd similarly be incorrect to do the reverse and impose the instructions here onto other courses.

Even if you go back to the material upon which I based much of my instruction - Dynamic Sketching - you see similar inconsistencies. Peter Han would generally have people draw their super imposed lines more slowly, prioritizing following the line, whereas I push students to execute their marks as confidently as they can, to commit to a single trajectory even if it deviates from the guideline. Neither is wrong - we just have different goals and priorities.

I hope that helps. Anyway - congratulations on completing Drawabox!