Hi! So, it was a good effort, still, there are some things I wanted to show you. Here's the demos.

So, on the first image I tried to make the same drawing as you, over the original picture. If you notice, the eyes are big spheres which get covered by the eyelids, instead of jumping straight to replicate the form we see. The blueprint of the muzzle is simplified, but from it comes the boxy, solid form that is the muzzle itself. After that, (there's the divide between jaws missing, sorry about that) you should add the soft masses of the cat "lips" and nose. With animals you have to be very careful, because things like those (which you represented on your drawing as simple spheres) are actually quite flatter than they appear, and most importantly, they follow the form that's underneath them. That's why on your drawing, that section of it looked flat. Think that those things are like our own lips, they wrap around the jaw, and all those solid forms.

Then I made the outer "cage" or "helmet", based around the muzzle footprint, and the eye sockets. After that, the ears (which are supposed to come from a place we can't see, but you're supposed to draw through the forms) and that's it. The lower neck is a total mess (I did the drawing on Paint), but even like that it could be fixed adding masses.

Then I did the same thing over your drawing, using most of the same lines you did. The corrections are self explanatory there (I did write footprint instead of blueprint though) You can see that, while I used your same lines on the muzzle, I still ended up needing other lines more similar to the ones on the original photo. These forms change from one animal to another, but with enough care you can see them through the skin and fur of the animals (as well as the form of the eye sockets).

Other than that, the process was basically the same as in the last photo. I did make the jaw subdivision, I added an extra mass on the bottom to better replicate the form on the model, and I made the outer "helmet" a lot smaller, because the original cranium was already big. It's useful to take some measure when constructing animals, that way the proportions don't get too wonky (that's outside of the course's requirements, of course).

In the end, you can see that, while far from perfect, the construction I made looks and feels more solid and threedimensional, thanks to constructing the underlying solid form, breaking it into planes, and then adding the soft forms over it. Again, the drawing was not bad, but it could be better.

Let's make another head, and try to find another angle for it. His one had kind of an awkward pose :P Take into account the corrections and be organized when you are constructing the head. Good luck!