Does the quorum rule for school boards stated in your December, 2007 response also apply to charter school boards?
It does NOT apply to charter school boards. Charter school boards follow the nonprofit model, which only requires a majority of the quorum present vote in the affirmative to pass something. So if it is a 7 member charter school board and only 5 are present, a vote of 3-2 passes. If it was a 7 member publically elected school board and only 5 were present, it requires at least 4 votes to pass a vote.
Charter school bylaws may also be more restrictive than the nonprofit rules. So if your charter school bylaws and/or your contract with the district require that you will follow the voting requirements and policies for the school district board, then you would have to follow the more restrictive rule.