Our superintendent has suggested the board have lunch together at an OSBA conference. I take it this would be illegal if we have a quorum or more board members present?
The law has an exemption for training events and conferences. You can have meals together, but you shouldn't discuss or deliberate on district business directly. You can talk about things you have heard while at the conference, but keep them general, and don't move into discussion of the direct implication for your district. An example would be talking about what you heard at the workshop and concluding by saying "this would make a good agenda item for discussion at a board meeting about how we can apply it in our district."