Rides on top of The Stratosphere (yikes!)
Adventure Dome at Circus Circus
SkyMania (do the 3-D Dodgeball. This is off the strip.)
Rollercoaster at NYNY
Fashion Show Mall
Hotel pools
Gameworks near M&M World
EAT! (there's a lot of food and buffets)
See a show. (i.e. Stomp, Blue Man)
Watch a movie (The United Artist 8 Theater is near MGM and The Orleans has Century theaters)
Cosmic Bowling (at Gold Coast. This is on certain nights only. The lights are down, lanes are lit up, and the music is blasted. Fun!)
Madame Tussauds waxed celebrities
OK, to enjoy some nightlife: Club Frozen75, which is actually in Henderson (about a 15-20 minute drive from the strip). It's open to those 14 and up, and runs every Friday and Saturday night from 8pm to 11:15pm. If this sounds like a little bit too much of a young crowd for you -- the club hosts an event called Zen 18+ After Hours which goes from 11:30pm to 2:40am. Both events cost $15. Check it out: http://www.clubfrozen75.com or http://www.clubfrozen75.citymax.com/index.html