We sometimes use that method in my graphic arts class. The teacher just calls it "green filming." You may want to check out a silkscreen supplier to get more information. Then again really photo emulsion is so much easier and you don't need to buy as much.
Funny, I've had a scrapbook for a while and haven't decided to start on it until now as well [this will be my senior year too].
First off make sure you take plenty of pictures. Even if it's just a regular day at school or a day around town with friends, bring the camera. Any meaningful experience that happens this year, save something from it [whether it be prom, homecoming, football game, spirit day at school, etc]. It might also help to write down a bit about those experiences too.
My 18th birthday is coming up in a little less than a month, and last night my mother suggested a music theme [since I'm soooo into rock bands]. We contemplated the possibilities, and all I've come up with are:
Watching music themed movies, taking "promo" pictures, actually creating music, writing songs, making mixtapes/cds [I was thinking about this as a party favor]
I've completely run out of ideas beyond those, and am not sure how many music themed movies are out there [that are worth watching]. So far all I can think of are School of Rock and Empire Records [which I have no seen].
Please provide me with any ideas you come up with for this theme, ahhh! I'll have to send out invitations soon if I want to have it before some of my friends go off to college.