Good job on finishing lesson 1. I think coloured paper is okay to use, as long as it's light enough that it isn't too hard to see your work. Now are you ready for your critique? Let's go.

Lines: Your superimposed lines are good, but you needn't scratch out your work if you feel you've made a mistake. Especially if it's only one group of lines. You don't need to hide the mistakes, especially when the rest of your work shows that you understand the lesson.

Your ghosted lines tend to arc slightly, perhaps try arcing them the other way slightly until you find a comfortable middle and your lines appear straight.

Ellipses: Your ellipses are pretty good, you seem to understand what you should be aiming for. You've drawn through your ellipse a few too many times on at least one occasion, remember that you only need to do it twice, but overall I don't have much to say.

Boxes: In two point perspective your vertical lines should be completely parallel to each other and perpendicular to horizon line. Next time you do the plotted perspective exercise, try taking time to make sure that your straightedge is aligned properly to these orientations. For your organic perspective exercise, try not to draw your lines multiple times, it makes things fuzzy and hard to see.

I hope this helps when you add these exercises to your catalog. I think you understand most things and should be ready to move on, congratulations.