The group focuses on advocating for sensible gun control in America.
The national organization was founded five years ago in response to the Sandy Hook Elementary School shooting.
Members said the shooting this week in Florida served as another reminder of why they meet every month.
Kathleen McFadden, volunteer, Maine Chapter Moms Demand Action, said "I think Parkland has hit a lot of mothers awakened the student voice. Children in this country should not be afraid to go to school every day. And I think you're seeing a ground swell of movement interest and activity in a long time."
Organizers said the group gives voice to the millions of Americans that are concerned about the level of gun violence in the U.S. They work to promote gun safety and gun control legislation. And they say they fight back against the quote "Rhetoric of the gun lobby that more guns make us safer."