Alrighty! Starting out with the cylinders around arbitrary minor axes, overall you've done a pretty good job. You've drawn your ellipses with a lot of confidence, keeping them smooth and even in most cases. Your side edges did leave a bit to be desired in terms of accuracy though, suggesting that you may not have been relying as much on the ghosting method (or at least not as completely and consistently) as you should have, which in some cases led to the lines not quite touching the circumference of the ellipse on one end. For this I'm not referring to cases where the ellipses were a bit looser, but for those I would suggest always aiming for the outermost ellipse being the one you attempt to draw your lines to. This avoids the issue of having lines existing outside of the silhouette of the form.

Overall you were pretty conscientious with your minor axis corrections, which clearly helped you develop your ability to align the ellipses well, though I did notice on one specific page that the alignments you were marking with your red pen were actually incorrect (as shown here). This appeared to be isolated however, perhaps it was just an off day.

One thing I am very glad to see is that you appear to be maintaining a pretty consistent relationship between the shift in scale from one end to the other and the shift in degree from one end to the other. That is to say, when the shift in scale is pretty minimal, so to do you keep the shift in degree pretty slight (shallow foreshortening). In the admittedly rarer cases where you made the shift in scale more significant, you matched it with a more significant shift in degree (dramatic foreshortening). Keeping these consistent is important, as the viewer will be able to tell something's off if they introduce contradictions.

Moving onto the cylinders in boxes, unfortunately it appears you neglected to read and follow the instructions correctly, in terms of the line extensions. This exercise is primarily focused on pushing students to develop their instincts for drawing boxes that include a pair of opposite faces which are proportionally square. We do this by taking the principles of the line extensions from the box challenge, and adding the cylinder to it.

The cylinder adds two ellipses, and with each of those ellipses we get three additional lines to extend - the minor axis line, and the lines established by the points at which the given ellipse touches its enclosing plane (we call these contact points). These lines only align to the box's own vanishing points when the ellipse itself represents a circle in 3D space that is resting on the surface of the box. Therefore if those lines are a little off from aligning to those vanishing points, then as we make adjustments to bring them more in line, the better we get at ending up with ellipses that represents circles, and therefore the planes that enclose them get closer to being square.

Because you didn't actually extend any of the additional lines relating to the ellipses, you entirely skipped this part of the exercise. While you no doubt got more practice at drawing the cylinders inside the boxes, and placing ellipses inside those planes, you unfortunately sidestepped the core focus of this exercise altogether. As such, I'm going to have to assign additional cylinders so you can demonstrate proper use of this technique. Fortunately, I will not be reassigning the whole 100.