You don't need to go to Africa for this safari party!
A little mosquito netting, binoculars, stuffed animals and lot of foliage (real or paper) as decoration and you're on your way to creating a safari in your backyard or in your living room. For added ambiance, download some jungle noises to play in the background.
On the invitation, request that guests come dressed as an explorer (in Khaki) or a favorite animal (or in animal print), or watch your own lions and zebras come to life by making face painting part of the party scene. They can even contribute to the scene by bringing their own favorite stuffed animal to add a personal touch.
If you'd rather get out of the house or have a group of smaller kids, consider the local zoo as an alternative.