After reading some of the suggestions, here's one: The first gathering should be on tools, fabric (especially using stash and clothing you no longer wear) and how-tos; this will separate the crafters into sewers and non-sewers. Both can have a part. If people are reluctant about sewing, they can still help by cutting pieces, etc. Include rudimentary rotary cutting safety!!!
The next class should be something they can start and finish in the time allotted, like a potholder, a hotpad, or something small.
Just act like this is conversation among friends, teaching your kids or grandkids, and you'll do fine! You already are looking for support on how to do this action, meaning you are more than halfway there. Blessings will follow...