These are the valentines I made for my oldest's class. We used glow bracelets that are sold at Michaels for $1 for 10. I found the font by googling "Star Wars fonts." The pinspration was from this site. I used a lego Starwars sticker rather than a scan of an actual lego. Darth Vader's lightsaber is visible when you remove the glow stick.
After we made these, I found this Yoda design which I think is adorable.
Both of the links have the file to print out- just in time for Valentine's day!