This may be a silly question, but what is the etiquette of high school graduates giving gifts to other high school graduates?
I understand friends and family members who are not graduates typically give gifts to the grad they know, but I’m not sure of the etiquette regarding grads gifting other grads, or if we just celebrate graduation without worrying about gifting one another.
Like your family giving a gift to someone? Or you giving a gift to your friend?
If we were invited to the party for a classmate of S1, we gave the grad a nice card and a check for $20.14, as in Class of. Obviously, a family member would be a different story. Seems like a nice gesture and it didn’t break the bank. I’ve also seen a shirt for the college the kid will attend, but they may already be fully outfitted! 
If someone is giving a grad party maybe get a small gift. Doesn’t have to be big at all.
But no gifts in general. You all just celebrate the occasion together and enjoy the moment!
Think of it as a huge birthday for a bunch of people. The gifting is done by people outside the circle.
gouf78 put it well ^.
D did not have a high school grad party, but attended several. Usually the kids did not give each other gifts.
For his grad party S was pleased just to have friends show up to enjoy the time together. He did receive a couple personalized gifts (inexpensive art supplies, like a charcoal pencil or a single brush) from his closest friends. Only family friends and relatives actually gave $ or gifts.
I think it’s not appropriate to show up empty handed so a small gift of around $20 would be fine.
Or a card. You don’t have to be crazy materialistic.
For my friends who graduated this year, I gave each person a card (personalized- I wrote each of them a nice message) and a gift certificate for a small amount to Amazon, which helps all college grads.
When I graduate this year, I’ll probably only give gifts to the people whose grad parties I go to.
I think if someone is really special to you, you should be able to give a gift if you want. You don’t have to give it to them in front of a lot of people, but in general I’d say I’m in favor of it. Generally I’d say the niceness of the gift itself should correlate to how close you are with that person; as long as you keep that in check, you should be fine.