Definitely a great start! Great idea to work on improving over the summer.
I would also add to the comments people have already posted, when you ARE ready to move on to shading, you do not appear to have the control over your pencil needed to produce a variety of subtle shades (although that may just be a bad scan.)
A simple exercise you can do pretty much anywhere, even while riding the bus, is to draw some boxes on a piece of paper and then try to fill every box with a different shade from your pencil, from lightest to darkest. See how many boxes you can still get a different shade into! There's actually a downloadable workbook for this exercise you can get by signing up for our mailing list, too. :)
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