I'm chair of a "Friends" for a secondary school. The principal is currently on our committee and has amazing ideas.
One of these ideas is that when departments in school request funding for a project etc, they also have to demonstrate support for us. The idea being that if staff want funds raised by the hard-working parents, they can show support at events.
We've just managed to snag a couple of new committee members, so at present we have about 7-8 regulars. I do have contacts for some who are willing to help at events, but who can't commit to regular meetings, etc.
We all have different evenings that we can't make, so we arrange meetings to vary the night of the week so we all get a turn to attend.
Also, we have quite a few email discussions, which actually helps a lot.
Finally, I'm looking into improving our documentation, so that we can all access minutes, agendas and things like templates for disco tickets, letters to parents for events, risk assessments for the disco or other events, and so on. I seem to have inadvertently created a Dropbox account so may use this to give all the committee access to this stuff, so that if one of us has to leave then the rest aren't having to redo it all from scratch.
We've started planning the Xmas fair, and we've divvied up the initial tasks. I think the point made previously about being specific on the kind of help you want is a good way to go, eg help run a stall for 1 hour, etc.