I hate to say this, but I think you may have missed some important concepts when working through this challenge. Looking over your boxes, they can be divided up into two groups.

One is the majority - boxes where you appear to be trying to keep your lines parallel - physically parallel as you've drawn them, not just parallel in 3D space (and therefore converging towards a vanishing point. The problem with this is that you're totally rejecting the principles covered in the instructions for the challenge, as well as the stuff taught back in Lesson 1. Instead of thinking about how these lines are converging towards their shared vanishing points, you're not considering the existence of any actual vanishing point. Because of this, your lines run roughly parallel as drawn on the page, and sometimes even end up diverging as they point away from the viewer. This is wrong. When drawing your boxes, you need to think consciously about the vanishing points each set of parallel lines (that is, parallel in 3D space) is meant to converge towards. Even if that vanishing point is faaar away, it still needs to exist in your mind, and you need to strive to point your lines towards it.

The other group, of which there are far fewer, actually do converge. For example, #1 falls into this group, as do many on this page. This is a move in the right direction, but you do still need to work on getting each set of 4 lines to converge consistently towards a single point. That means that when you're drawing a line, you have to think about all the other 3 with which it shares a vanishing point. It's easy to get caught up in thinking about them in pairs (like thinking about the lines that share a plane) but this will result in the convergences being inconsistent.

I think it'd be good for you to draw another 25 boxes at least, and demonstrate that you understand what I've explained here.