[mdturnerphys]

"high schoolers and college students in the sciences or engineering" - The problem is that your target demographic has no money :)

[MichaelCrawford]

They like t-shirts though.

Try making one of those posters with the tear-off tabs, with your URL on the tabs. Post it on college campuses.

If you get enough t-shirt sales started after a while the word will spread on its own.