A local environmental group has less volunteers than the national group which means less help, but it helps to get more actual spending funds
a national group has many volunteers from around the country, but funds are usually to low to actually pay for the cause since most of it was used to pay f associations
PRO- A pro for a local group would be that you can clean up your own community and notice the difference and also it is close so you won't have to travel a billion miles.
CON- A con for a local group is that you can only help the community and since a community could be small, based on my own, it wouldn't take a long time to do the service if there were a decent amount of people.
National:
PRO- You would be able to help outside of your community and you could meet some new people.
CON- A con for a national group would be that it could be far to travel and you would probably have to do research on the service and where it is before going.