Here we have The Star Wars Iron-On Transfer Book, uh....book, copyright 1977. It is in near mint condition, as I never actually used any of the iron-ons. I was aware, even in 5th grade, that there was something sort of uncool about wearing such a t-shirt. I would have been way too self-conscious. Nonetheless, I did wear a "May the Force be with you" shirt in 5th grade, so I'm not sure why I would have been embarrassed to wear one of them. God knows, some of these images were on an awful lot of shirts once the merchandising maelstrom was unleashed about a year after the film's original release!
You can't say they didn't warn us! They weren't messing around.