Our Principal is not mentioned at all in the organizations by-laws. Is she automatically considered an ex-officio because she's the principal or do we have to have that written in to the by-laws? Does an ex-officio have voting rights on the executive committee? We do know that she has voting rights at our general meetings as a member of the school administration.
Thanks in advance!

No one is automatically considered an "ex" anything unless your by-laws state it. An "ex-any-position" only has voting rights if your by-laws grant it.

Your by-laws determine who is a member (generally speaking) and who specifically serves on the Executive Board. Voting rights should also be spelled out.

Whether you consider your principal an Ex-Officio ("by virtue of office") Board member is up to you, but he won't have voting rights unless stated in the bylaws.

Note - your bylaws sometimes give you the authority to add voting members. One group I was in could had the officers, school reps, and chairs of stnding committees on the board. Plus we could add others with a % vote approval. At the first meeting of the year, we'd add in the ad hoc committee chairs and parent reps. These positions changed from year to year so we didn't want to keep changing the bylaws.

But the principal's role should be fairly consistent. You may want to address it in the bylaws.

thanks for the info Jewels & JHB. Very helpful.