This is a truly amazing oasis in a sea of cheese and debauchery. Since we were sans little wee one on our naughty adult vacation to Sin City, we decided to pop over to the Springs Preserve and check it out. It's a relatively new desert botanical garden and learning center. Hubby is a science teacher so he was WAY excited to get his science groove on.
We went a little later than expected and only had a couple hours to spend but we easily could have spent at least 4 hours wandering the hiking trails and checking out the cool exhibits. Basically this attraction has three parts...origin experience which has tons of cool interactive activities, films, and a little zoo of desert life, Desert Lving Center which is all about conservation, and Gardens/Trails which is a bunch of interconnected trails. It was really cold when we were there so we didn't spend as much time as we like on the trails.
If you have some time and want to get away for a bit from the smoke and vice of the Strip, check out the Springs Preserve. It's really lovely.