Fun things to do in Las Vegas with your children are:

*Take them to see a show - some of the Cirque du Soliel are kid friendly. I took my kids to Mystere almost four years ago and they are still talking about it. There was nothing inappropriate in it. They loved the big guy dressed as a baby!  Many of the comedy and magic shows are kids friendly.

*Arcades: almost every hotel has one. The one inside the Excalibur is huge and they also have a diner show call Tournament of Knights that kids enjoy.  It is like Medieval Times.

*Go see the Dolphin habitat at the Mirage.  I was surprised at how great this was when we went.  They have more than just dolphins to see.

*Take them to the M & M Store in front of the MGM casino and hotel.  They have a very creative walk through "M&M factory" on the 3rd floor.  Once you walk through you sit in a little movie room and watch a short 3d movie.

*Go to the pool.  If your hotel pool is not that great you can pay to go one that is.  Such as the one at Monte Carlo or Mandalay Bay.

*Circus Circus is a must, they have a great arcade, an amusement park, and circus performers every hour. If you decide to stay there I would ask for the new tower. My friends stayed in the older part and were not thrilled with the room.

*Water showin front of the Bellagio as well as their atrium.  The water show is always changing.  Even if you go several times in one day you should be able to see several different shows with different music.  They also do the atrium up nicely and change it all the time.  It is fun to walk through and get pictures. Both of these things is free.

*Pirate show in front of Treasure Island is always fun.  It is not as kid friendly as it used to be.  If your children are too young to understand certain innuendos than I encourage you to go.  This is free, but crowded.

*The Volcano in front of the Mirage hotel and casino is fantastic.  They have updated this recently and now has music and fire explosions and of course the volcano erupts.  This too is free, but not terribly crowded now that it covers more area.  You will want to watch from the south side.  

*Lied's Children's Museum is not far from the Fremont Experience.   My kids had a lot of fun when we went.  There are lots of different hands on activities for a variety of ages.  My daughter especially like the tornado experience!