Excalibur has boardwalk games, Circus Circus has amusement park games, Stratosphere has a roller coaster on the top of the hotel and the M&M store has fun things.
My 16 yr old niece loved going on the Eiffel Tower Ride @ the Paris hotel. My 13 year old daughter loves the rides at the Adventure Dome at Circus Circus.
Go to Circus Circus and play in the arcade. Stratosphere Casino you can take a ride to the top. They also have a roller coaster. The strip has shopping.