Congratulations on completing the 250 Box Challenge!

You did a really well overall, your boxes were pretty consistent in their construction. I can see you took your time and were careful in your construction. You also do a much better job of getting your sets of parallel lines to converge more consistently towards their shared vanishing points, good job there!

One thing I noticed throughout your work here is that you drew your boxes rather small. The instructions say to try and keep your pages at around 5-6 boxes per page, which is exactly what you did. However, the reason for this limit is so that you have room to draw your boxes at a larger size than you have. Drawing bigger helps engage your brain's spatial reasoning skills, whereas drawing smaller impedes them. Just keep that in mind in the future and make the boxes bigger next time. I can also see that you didn't really experiment much with adding weight to your lines as shown here. These are just a couple of small steps you can take in your warm ups to really get the most out of the exercise.

Finally while your convergences do improve overall I think this diagram will help you further develop that skill as you continue through Drawabox. So, when you are looking at your sets of lines you want to be focusing only on the lines that share a vanishing point. This does not include lines that share a corner or a plane, only lines that converge towards the same vanishing point. Now when you think of those lines, including those that have not been drawn, you can think about the angles from which they leave the vanishing point. Usually the middle lines have a small angle between them, and this angle will become negligible by the time they reach the box. This can serve as a useful hint.

As I said before, you did a really good job on this challenge overall. If you keep in mind what I have said here you should continue to improve over time.