Congrats on finishing the challenge!

Overall - Make sure your hatching lines are not wobbly. It's ok if they fray on one side, but make sure they are smooth. Also, draw bigger boxes! It's hard to see where you made a mistake if you don't have much room to draw.

You also need to make sure all angles of your Y are above 90 degrees. Boxes like 219, 225, or 226 look slanted or have their solidity undermined because the front Y has an angle of or below 90 degrees. I think you should also push yourself to draw a greater variety of shapes and orientations. I would recommend checking out the Y generator mentioned in the lesson for ideas if you haven't already.

Here is a diagram of different box orientations (challenge boxes should always be drawn from imagination though) -> https://imgur.com/Kqg6uMX

Convergences - Your convergences improved over the course of the challenge, however a lot of lines still look parallel, especially the ones that are vertical (heading toward the top or bottom of the page). Remember that when you look a box the edges converge in all three directions, including up/down. I think otherwise your convergences are quite nice.

A good diagram -> https://i.imgur.com/8PqQLE0.png

Inner corner - Your inner corner is often diverging or converging way too quickly. Compare the slope of your Y line to the slope of the mark you're planning. For the inner corner lines they should be pretty similar, near parallel. Don't draw a line from the inner corner to the center of the Y, this will pretty much always be the wrong slope. Keep in mind the inner corner will also not have any angles below 90. This ordering can help you improve your inner corner quickly -> https://imgur.com/FGdtVwm

I think you're ready for lesson 2. You can keep practicing boxes as a warm-up exercise. I hope this feedback is helpful! Congrats again :)