M.M.
Try and explain to her that she is going to have the best of times there and that just think about her own little space! she is getting to become this big girl and make it kinda like a fanasty story....she has become a princess and needs to go to her castle to become queen one day! she will meet and greet other little girls and boys and have so many friends....also you can become friends with a few moms that are there and make a playdate with them to get her more comfortable too!
have the kids sit in a circle and show and tell, have them tell the moms what is so good about child care or school....even once you've become close enough to someone get to have a sleepover with the children. just a few different options and ideas here if you'd like to use them!
Hope it works well! ~M.