While not the question of the day, if the teens have an interest in cars, look at the Shelby car museum and factory. Also, hiking around red rock.

Vdara has no pool action to watch. While I have no personal knowledge, the MB has more pool activity to watch. MB also has the shark tank to view.

For traveling up and down the strip, you might look at a day pass on the Deuce bus that just does a loop up and down the strip.