Starting with the cylinders around an arbitrary minor axis, Your side edges and ellipses are drawn confidently and smoothly, you've experimented with the rate of foreshortening (something that a lot of people seem to neglect, despite it being in bold in the instructions), and you're doing a great job of checking for minor axis discrepancies which is important to ensure you do not plateau in that area. Overall, you're demonstrating an understanding of how these forms change in correlation to how they're oriented in space.

I was a tad bit concerned with your first few because those cylinders had little to no foreshortening at first but it seems like you got the message from that point forward. The reason why we ask for varied foreshortening comes down do the ways in which foreshortening manifests itself on the forms we create. It does so through the shift in scale (where the back end is smaller than the end closer to the viewer) and the shift in degree where the farther end is relatively wider. This is something students seem to understand not consciously but on a gut-feeling level, and others have trouble grasping the concept that these shifts occur in conjunction with each other.

A dramatic shift in degree with minimal shift in scale tells the viewer two contradictory things: that the length of the cylinder exists in the unseen dimension of depth, and the the length visible on the page is all there is. Similarly, a cylinder with a narrow front face but had dramatic side edges tells us that the front is facing away from us and the side is also facing away from us. Both can't be true, so we must ensure that both shifts exist together.

You seem to understand this as a whole - if not consciously, then subconsciously. Hopefully this explanation helps push this further into you conscious mind. Now, there were a couple times such as cylinders 42 and 48 where you got the orientation mixed up (hatching the wrong side, cylinders diverging instead of converging, etc) but I'll just chalk it up to some minor slip ups on your part.

Moving onto your cylinders in boxes, these are similarly well done. What we're trying to do here is develop our understanding on how we construct our boxes to have proportionately square faces regardless of the box orientation. To do this, we don't actively memorize every single configuration but instead we subconsciously develop that understanding through repetition and analysis.

The box challenge was all about developing a stronger sense of how to achieve more consistent convergences by analyzing the line extensions. Here, we're just adding three more sets of line extensions: the minor axis lines (which also happen to be one of the vanishing points), and the two contact points. We can check how far off these are from the box's vanishing points and this helps us determine whether the ellipse represents a circle in 3d space, and in turn how far off the plane was from representing a square.

In applying those line extensions quite fastidiously across the whole set you've been able to gradually train the way in which your brain understands those proportions, helping you get a better instinctual sense on the given orientation of the form. I'll be marking this as complete. Feel free to continue onto the next lesson.