Create one of a student or patron asking a question. Create one of those speech bubbles that has the question in it: "Native American?" Or "American Indian? Which one should I use?" You could replace the figure below with a photo of yourself to show that it is a question you, yourself, had, too.
Put Mission To Space by John Herrington in the display. If you have two copies (and you should!), use both. Show the cover, and, have the second copy open to this page (below). Beside it, on a poster board, call attention to the text in the book about his identity. Here's how that could look:
And here's how that same idea could look, using Cynthia Leitich Smith's Jingle Dancer:
Then you could have another poster that says something like:
I'd like to hear from librarians, and others, about this idea. Your thoughts?