Good arrows, but stick to the exercise: don't make them turn around themself every time. Also, keep your curves flowing, it looks a little bit "blocky" sometimes.

Great organics forms, keep them thick everywhere but that's good job.

Very nice texture analysis, you really understood the "cast shadow" concept.

For the texture dissection exercise, sometimes your textures seems flat (I'm thinking of the marble, paper, etc). Don't hesitate to break the silhouette, especially for stuff like feathers.

The forms intersections are great, but don't forget to drawing through ellipses when you draw a sphere.

Finally, your organic intersection is very good, and the shadows are mastered.

So, really good job generally, all the concepts of the lesson are understood and applied!