Hi,i just posted my 250 boxes challenge yesterday but i will give my critique about your homework.

Well first of all, you got a cool accuracy and the lines feels very smooth.

about the orientation of the boxes's lines they're good as well,of course some (especially the back interior lines) are a little of but that's pretty normal.

Now what i think could be better, it's those lines that you scribble as if you didn't like them.In those cases you should just let them be it's part of the process.

you seem to have forgotten to ''shade'' one side of most of the boxes as you forgot to just take one stroke in the interior lines

At last i want to emphasize that you realy did a great job, and to give more attention to keep things more neat

so... yeah, bye