Organic forms:

-Don't make it more difficult on yourself, these should be simple "C curved-like" shapes.

-Make sure you vary the openness of your ellipses as they turn away from the viewer, there is not much variation.

-When doing contour lines, draw them from your shoulder and, as mentioned before, vary their openness

-I suggest you overshoot your curves first before attempting to be accurate. It is more important that you get a feel for the three dimensionality of the form rather than emphasizing precision.

Arrows:

-I would advise against trying something like swooping your arrows , there are other things you should work on before attempting things like it.

-These arrows still feel like there are flowing through a page and not existing in a believable 3D space. See this. and compare it to yours. The way I approach the arrows exercise is I draw a swooping line that grows as it approaches the viewer, then I'll draw lines down coming from the edges (growing longer as they approach the viewer) and then I'll simply connect them. I suggest you try this and see how it goes.

-You could also be more conscientious about the gradient hatching. Think about how it'll get tighter as it reaches the curve.

Textures:

-Good intro to texture, especially the tortoise skin. (though next time i would suggest filling in the areas as it does appear somewhat scribbled.)

-Think about the shadows and the forms that are casting them.

-On the dissections, make sure there is less concentration of detail on the middles than on the edges.

Form Intersections:

-Try and consider the surfaces of these objects and be more deliberate about how they interact.

-Watch your line weight, there is visible shakiness and hesitation.

-Stay away from extreme foreshortening. There is a cylinder on page 3 at the bottom right that implies a sense of scale that is not consistent with the other forms.

-I would advise against adding contour lines to your cylinders and spheres as this will just continue to clutter your drawing and doesn't really add anything of value.

Organic Intersections:

-contour lines look much better here than they did at the beginning

-shadow shapes are arbitrary and don't follow the surface they are being cast on

You are starting to get the concepts you are meant to learn in this lesson, however in order to get the most out of it you should stick closer to the instructions.

Do

-2 more pages of organic forms

-2 pages of arrows

-2 pages of form intersections

Best of luck

-Slyx