Did it in high school too and enjoyed it a lot. I also designed almost all of the T-shirts in class. From field trip uniforms to intramural uniforms. Though I just did the design, not the actual printing.
I tried 3 styles when I did em myself. One using the light-sensitive kind of paste which was more trouble than it's worth LOL, but also makes for the most complex designs.
Another is green film which is a bit better but still a bit clumsy when it came to cutting out the designs.
The one I liked the most is the more primitive one. Simply cut out something in cardboard and spraypaint/squeegee textile paint on it. Also experiment a bit. Of course you won't get the same complexity as the other two, but it's fun. An exercise in minimalism and making good designs even when you're limited by not being able to detail. Plus it looks more street-artish than the other two.
I've made um... a scorpion design, a jolly roger (with scimitars and a fanged skull), a soldier in full fatigues with stencil type text, an evil 'emoticon' type face with graffiti style text, and a barbed wire 'necklace' meant to be printed around the collar.
My more recent designs were computer printed though - a burning usb jack, a stream of binary numbers flowing down a stylized layout of a workstation, a tree frog, and a silhouette of a native filipino warrior for my brother-in-law's airsoft team. I have a copy of that. Here:
Computers get better results at high quality but doesn't have quite that 'customized' look to it.
Anyway, I like the design your planning. I don;t think you'd be able to duplicate those brushstrokes on the cheeks though. Maybe if you do it afterwards? Kinda like postprocessing or something.