They look like some type of Psathyrella, but its not possible to say unless you provide the more information (and even then it may be difficult)
Photograph the top of the cap as well as the gills and stem in detail.
Take a spore print! And describe its color (VERY important!)
Describe what part of the country you found them in, As well as what they were growing on and how they were growing there.
Describe cap: (conical, umbonate, etc..)
Describe stem:
Describe gills:
Describe Spore print color:
Describe what they were growing on (habitat) (grass, wood chips, pine-straw, dung, etc...)
Describe what state and country you found them and what time of year you found them growing.
If this information is provided you will get an ID.
-eg