I'm considering applying to become one of these. School governor would probably be a local state primary and the trustee opportunity I've seen is with a local branch of Homestart. I've not done either role before but have worked in the charity sector previously, in office functions rather than directly with clients. Of course, I may not get either, but before I start filling in application forms, I'd be interested to know the experience others have had in either role. Thanks!
The only thing I'd consider carefully is not becoming a trustee of a charitable trust. The trustees have a great deal of personal liability with these. If it's a charitable company or a Charitable Incorporated Organisation, then trustees' personal liability is strictly limited (usually to £1).
I have done both and have found them both really interesting. I would prefer to be a charity trustee as I found the school governor role was just needing too much of a time commitment. I am trustee to a charity that I am personally very involved in so it is good to see it from all sides and be so involved.
I think that the demands of being a school governor depend on the school... I became a governor at an academy which was very well-established and very well-run, with excellent results, happy staff and happy students - there really wasn't a lot to do. I then joined the board for a new academy (starting with year 7), and they were keen to have much more involvement, which was much more rewarding. I've since moved out of the area, but am definitely considering volunteering to be a school governor again.
I'd suggest that if you have a particular school in mind, get in touch with the head teacher, have a chat about whether the school needs more governors, and what their expectation is, in terms of on-going and long-term commitment.