For the first 50, while your lines are generally clean, I did see a few instances of arcing, like box 7, box 29, and box 45. I also noticed the odd line that appeared to be redrawn, like box 17 and box 36.Your convergences show decent accuracy, though I did see some lines pair off and converge towards two vanishing points, like box 5's blue lines, box 25's red lines, and box 46's blue lines.

For the next 50, your lines show improvement. While there are still some instances of arcing, like box 60, box 72, and box 98, most are less dramatic. I also noticed fewer lines that appear redrawn.

For reasons that I'll address at the end, I had difficulty assessing your convergences. However, what I saw showed some improvement, though there are still instances of lines pairing off, like box 55's red lines and box 71's red lines.

For the last 150, your lines show further improvement, though there are still some instances of arcing like box 112, box 163, and box 219. Since it appears throughout the challenge, I recommend reviewing the information in this section and ensure that you are practicing the proper technique.

As before, it's difficult to assess your convergences, but I do see some more improvement. However, there are more instances of lines pairing off, like box 150's blue lines, box 176's purple lines, and box 243's purple lines. In these boxes, the inner lines (green and orange in this diagram) diverge instead of converging at the vanishing point. Keeping in mind the angles of neighboring lines can help when planning the box's construction.

As an aside, some of your boxes get a bit small on the pages, like box 19, box 55, and box 240. Drawing larger boxes is more effective for practice, as it'll help you engage your whole arm from the shoulder, and will engage more of the part of your brain that processes spatial reasoning.

Also, in the later pages, some of your boxes ended up a little similar. For example, this page's boxes were all very similar in size, shape, and angle. Boxes 211 through 220 also had very similar angles and shapes. While having similar boxes appear throughout the challenge is normal, drawing the same box back-to-back isn't ideal for practice. Varying the sizes and shapes within a page is preferred, as it gives us more practice visualizing and assessing different perspectives.

A more significant issue was how you drew line extensions. While the first 50 were done correctly, most boxes from box 56 onward had some lines extended in the wrong direction. For example, all boxes on this page and this page have at least one set going the wrong way. Boxes 102 and 103 has lines extended correctly, but the other boxes on the page have mistakes.

As shown here, lines should be extended in the same direction as the branches of your original Y shape. Line extensions are a key part of this exercise, as they enable us to look out for any trends or habits to correct. Drawing them incorrectly makes it difficult to assess any trends that might appear. For that reason, I'm going to assign you revisions for 25 more boxes with line extensions; 10 in the style of The Next 50 and the rest in the style of The Last 150.