Wow I have been to Vegas many times and these guys gave awesome advice. Something I also liked doing was going on some of the rollercoasters in New York-New York and Stratosphere. I know too you can find helicopter rides that can take you for some amazing rides over the strip and I personally liked the gondola rides in the Venetian as well. So many fun things to do!
Kat and Kali,
I'm sure you'll enjoy Caesar's Palace, as like I said, it has the best shopping mall in town--including even statues that come to life (automated), and special shows, and major restaurants in the mall, and its directly connected to the casino and sports book betting areas. Caesars is also where Elton John is appearing (I think he's over his recent pneumonia attack, and so his show should resume soon).
Unfortunately, I notice that the forecast is for a very hot June in Las Vegas and Arizona, so keep this in mind when at the pool or visiting Death Valley, Sedona, or the Grand Canyon