It's really good, just try not to repeat your lines: stick with ghosted lines and draw your first line confidently. Just something you might have missed from the instructions: (1) in the plotted perspective exercise you should do everything with a ruler, such that every line goes right into the vanishing point; (2) in the rough perspective exercise you might want to draw a line between your square's lines and the horizontal plane (not the vanishing point! the point is to see how accurate your rought perspective is!). Before going to the 250 boxes challenge, I suggest you retry these two exercises. Good luck!