I'm fortunate then, I spent a bit of time with North West Scale Modelers, they're not actually an organization. We probably have as many 'members' over 75 as we do below 20, but the main group seems to be 40-60 yo. Many IPMS members, but we're not an IPMS chapter. No rules, no officers, no dues, every couple of years some person volunteers to be The Person Who Talks Too Much (TPWTTM) to ringlead the monthly meetings. Announcements, February model display (no contest), 6 questions (usually airplane trivia), show and tell, next month's topic (October is probably orange and black
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). Some of us hang out in the back of the room and actually work on kits during the meeting. We meet at the Seattle Museum of Flight on First (free) Thursday, part of our give back to MOF is a quarterly display of our models in a special display case that may well highlight a museum feature.
Seattle IPMS meets on a Saturday AM and I can't get to the meetings, but they're mostly Seattle laid back and feature a long show and tell session. Fair distribution of young'uns, but most are children of members...
I'm on TDY in Portland and get together with OHMS, an actual IPMS chapter. They meet twice a month, one meeting is a formal meeting with club business, show and tell and a judging of displayed kits. The other meeting is a build night, nothing formal, just guys working on kits and talking about just about anything... Several youngsters show up from time to time, but they're well outnumbered by the over 60 crowd.