Things you did well:

• I think your overall consistency did improve over the set

• Your linework is looking decent, though there's still a touch of hesitation where you're not drawing as confidently as you could.

• You've mostly stuck to the idea of drawing one mark per line (rather than trying to correct perceived mistakes - you only did that a couple times).

• You drew through all of your boxes, which is good for establishing an understanding of how they exist in space as 3D forms rather than just as lines on a page

Issues:

• You only applied the line extensions to a small handful of the boxes you drew. The point of the line extensions is to show you were you stand to improve, so you can focus on that in your following page. By making the decision not to follow the instructions as they were written, you seriously diminished the impact of the month you spent working on this exercise. You still clearly benefitted from the exercise, but not as much as you could have.

• Try to incorporate more variation between boxes with shallow/dramatic foreshortening. Looks like you stuck mostly to the shallower ones, where the vanishing points are very, very far off. In fact, with a many of them it does look like you may have focused more on keeping the lines parallel to each other instead of thinking about how each line converges with the lines it runs parallel to (in 3D space). Even when dealing with shallow foreshortening, you should still be thinking about how those lines converge towards a vanishing point as you draw them. This is what applying line extensions forces you to think about.

• I'd probably try to draw bigger. This'll help you use your whole arm and avoid issues that come from drawing from your wrist or elbow.

You absolutely completed the challenge, so I'm going to mark this as complete, but I think you did yourself a disservice in not doing one of the major components of the exercise.