Sam's Craptastic Sketchbook - Constructive Criticism, Please!

[Sam I Am]

Hello, everyone! I'm Sam. I'm not really new here, but I left for a while, and changed my username when I got back. So I figured, new name, haven't been here for a while, why not start a new sketchbook?

..Unfortunately, I haven't gotten much better since I left. I lost my motivation for a while, and I'm only just getting back into it. I'm determined to stick with it and get better now, though.

So, here's a few of my sketches...






Constructive criticism is greatly appreciated.

[Sam I Am]

I drew this this morning, with a photo reference. If you could let me know what you think about...well, anything about it, but especially the hair, I'd be grateful. It seems like I always have a tough time with hair. I'd also like any thoughts about the shading, or tips about shading in general, as I also struggle a bit with that.
So...any comments?

[Kriss_Kringle]

Hi Sal,about the last piece let me start by saying that the hair is pretty messy.Think about when a woman combs her hair until it looks great.Sharpen your pencil as much as you can and start drawing the hair,the more lines you add,the better it will look.There's no real formula for drawing hair,you just have to practice,so stick with it.
Now about the shading,it's all over the place!You need to learn hatching and cross hatching if you want get better at it.Start drawing spheres and then shade them,gradually adding layers until it looks like realistic shading.Don't be afraid to use your finger to smudge things out and add bits of light with a kneaded eraser after.
You seem to have a good eye but you need to practice more to get the hang of it.Good luck!

[Sam I Am]

@Kriss_Kringle - "The more lines, the better it will look" was pretty much what I was thinking; I'll have to practice more. As for the shading, I really do need to learn hatching and cross hatching. I'll definitely try it with the sphere. Thanks for the tips.

[Sam I Am]

(Started this yesterday, finished it today, with a photo reference.)
I tried to add more lines to the hair for this; I think it looks a little better than the last one, but, as you can see, there's still room for improvement. I also attempted cross hatching on this one...can you even tell? I think I might have put the lines too close together, but I'm not sure. Thoughts? Opinions?

I tried hatching and cross hatching on some spheres and cubes before I did this, too, but I haven't scanned them onto my computer. I might post them here later. I'm working on some hand studies at the moment, and I will have those up later today, or tomorrow morning, at the latest.

[Tagachi]

You are off to a good start.
There are some fundamental drawing concepts that I feel you need to improve on.

What tomes of knowledge have you read?

[Sam I Am]

Not many, to be honest. I've looked into Loomis a bit, mainly for proportions, but other than that...

What do you think I should improve on?