You probably need to refer to your bylaws first. We have a requirement that office bearers can be removed if they fail to attend 3 meetings without explanation.
As for the checkbook, I'd be contacting the bank to remove the treasurer as signatory. We just had a situation where some checks went missing and the bank advised us that the only really secure way to handle it is to cancel the account and reopen a new one to prevent fraud.
Make sure you follow the rules. It could be a minefield.....don't the school know where the parent is? Is the child coming to school each day?
Our Treasurer has not shown up to our meetings. He has the checkbook, and we can not get ahold of him or get the checkbook. Crazy! How do you releave a person from the board. Is it just a vote?
