cookie17 said: "Hadestown is a must see. See it now while the original cast is still there - Andre DeShields is a legend.
I saw Moulin Rouge and loved it for the costumes, choreography, and the lights - it's a big spectacular show.
As long as you pick mezzanine seats you should be able to see both."
First of all, congratulations on your achievement. You should celebrate.
I second re Moulin Rouge. A celebratory musical full of life, beautiful to look at, loads of fun, with great splashy production numbers. Will win a bunch of Tony's come June (IMO). I don't agree re Hadestown. It may be a great show (I personally disliked it a lot, although my wife liked it), but it is very dark and IMO dreary. Personally I would try to see something that is fun or truly great.
Be aware that Six is 70 minutes long. I personally have problem paying Broadway prices for a 70 minute show. Might be great if it started at 6, so I could catch a second show.
Given your age, I think you should consider West Side Story, even if it is not a joyous show. I don't see it until May, but it sounds incredible, based on many of the posts this board.
Of course, we don't know what you have seen already...is Mean Girls the only show you have ever seen, or just on Broadway? If ever, then I would personally recommend that you consider Chicago or Phantom or Wicked. There is a reason they have run as long as they have. You really don't need to limit your choice to something that is relatively new. With Chicago or Phantom, you can get pretty good seats discounted (go to Playbill.com for one list of discounted shows) for reasonable prices, especially if you get them well in advance.
Again, congratulations.