There is a group of very active parents at Hyattsville Elementary. You should call the school and ask the school secretary to pass on your name and number to the PTA leadership. I'm sure you'll get a response. My kids don't go school there but I've seen and heard about the events the PTA has organized in recent years and been impressed. They do fund raising things (book sale, plant sale) and school clean up and landscaping days. I don't know any more than that.