You might use the meeting to talk about why you feel like a PTG would be helpful and express some of the things you hope to accomplish. (I wouldn't make that list too long.) Then open it up to discussion -- other parents are likely to have ideas and suggestions. Letting them voice those and making this session interactive will help get people more excited about the prospects of a parent group. Before it's over, ask for volunteers to be on an organizing committee -- not officers at this point, just people to help set direction and get things organized. If you leave with a handful of people who will help get bylaws in order, etc., you'll be in great shape to elect officers at back-to-school time and move forward.
Good luck!
- Craig
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