Just last night got back into watching skateboarder videos. The hate that they get, regardless of their age, is just sad. Leave the poor skateboarders alone. It's not up to citizens to handle it. Call the authorities and let them deal with it if you think there's a problem. But even the cops are dicks sometimes:
I love how people freak out at guys like these. I know that if I saw someone like the old lady trying to talk to kids like that I'd step in myself. It's not up to those people to lecture kids, it's their parent's job. If they have a problem take it up with someone else, you don't run the law
If a skateboarder manages to make it through a large square of grass, (which is what I assume your lawn is made of ) then he deserves to skate on.