My DD is graduating 8th grade this year and I haven't heard of any celebrations as of yet. I'm ususally the last to know. The school system has held a "graduation ceremony" for several yrs, although not when I attended years ago. It is held at the middle school (6th-8th) auditorium. The 8th graders also go on a field trip in May to Williamsburg, VA and DC for (4) nights. This cost $400 plus spending money, enough of a gift for me.
I think you know your daughter best and only you can know what she will like. I do like the ideas of the bonfire and the jewelry. The jewelry especially so that she can hold onto it as a keepsake. Why should you even need a reason to throw a party, I say enjoy the moment!!!! To heck with what everyone else thinks.
I take the opportunity when I'm with them to connect and talk to them.
I make a scrapbook of their trip with their mom.
My kids are DS20 DS18 and DD15.
All of them had great trips and they talk about their 8th grade trip all the time.
We made wonderful long lasting memories and I know that it made a difference in our relationship.
MAKE MEMORIES! MAKE A CONNECTION! MAKE A DIFFERENCE!
I really think the above says it best. The most important thing is making memories and connecting with your child. I hadn't even thought of buying her a gift for her 8th graduation, but I tend to lean toward the spending time together idea. At least twice per year I have my girls make a list of what they would like to do all by themselves for an entire day with mommy (within reason, of course). They love this more than any gift I could give them. Having (4) DDs doesn't allow each of them much along time with mommy.
Good luck coming up with an idea and congratulations to your DD.
I think you will get alot of good ideas here.
OT: My DD14 also plays school FP softball and traveling summer FP softball. She had such a horrible season last year that my DH and I decided we would give her an incentive to try harder and focus more this year. We give her $5.00 for each hit (not on error) and $10 for each homerun. Last year she hardly had any hits at all, this year she has had ALL hits and (1) homerun and we have only had (3) games so far this season. At her age, money is a BIG motivator. I figure we would be giving her the money in some other fashion anyway, so why not make her work for it.

Her Bday is today and she is getting a new Catalyst bat. She has been wanting one for (3) yrs now, took me that long to pay for it!!!!!

FLAME AWAY!