If this isn't possible, get a redlight filter. No matter what you choose, this is pretty much essential for any astronomy trip. Almost no matter where or when you are, it gets awfully cold at night. Even in the middle of August, we've found people quite chilly during the night. Thus, you want to make sure that everyone brings blankets to keep themselves warm, and ideally some warm clothing as well.
Blankets are also necessary to lay on, especially for grassy areas.
Thus, you can just lay back, adjust the back of your bed to point your head at the right star, and look up. These are especially great for meteor showers, when you just lay there, reach for the soda and pizza at your side, and enjoy the quiet night. If people are going to be on the ground with blankets, tell them to bring pillows as well, or else they'll get their neck strained and it might hurt from the hard surface. Managing your group Different people like their astronomy in different ways. Others like to watch in silence, taking in what they're seeing and keeping it to themselves.