Taming Amazon discussion

I've written a young adult action adventure book and it's now listed on amazon. My issue is with the age range. From what I can tell, there's no "and up" option (like "10 and up"). I have to choose a range, like 10 to 15. However, there's loads of books on amazon that say "age 10 and up" or "grade 6 and up." Any ideas on how I do that?

You could just add it to the beginning of your book's description. I've seen it done that way.
Let me know if you need help with that.
Jim