Honestly, if your young promise rings are kind of stupid. A promise ring is supposed to be a sort of pre-engagement thing to signify your committment to one another, but at a young age chances are the relationship won't work out.
I got a 'promise' ring for my highschool girlfriend but didn't want to look cheesy and like a young, naive idiot, and so I kind of gave it my own twist. I bought the nicest ring I got afford at the time (only cost $400-500

) a few months into our relationship, and I gave it to her with a handwritten note tucked into the ring box. In the note I explained how much I loved her and that this ring would be my promise to her that for as long as he were together, if not forever, that I would always love her as best I can and treat her the way she deserved to be treated, like a princess. I made it clear that it had nothing to do with marriage or engagement, just my most sincere promise to cherish whatever time I had with her.
We lasted 3 more years after that, and she wrote that ring every single day until she moved away. I don't regret getting it for her either as I felt I was as mature about it as I could possibly be at 16 years of age.