September Mushrooms

Walking around my front yard a week or so ago, I came across a variety of different mushrooms growing in the "lawn". Mushrooms have been growing in several locations all summer. I would come upon them while walking to my car or getting the mail, etc. Going back later to take photos was too late. Either the squirrels had eaten the caps or they had turned slimy. This day, I stopped what I was doing, got my camera and took these photos. I find them intriguing. I know nothing of mycology, but hope to learn what varieties these are.