I think you should apply, but don't bank on assuming that not many people will apply. I can think of loads of people the job could suit: a university student, somebody whose partner works early shifts, somebody retired who wants to keep busy....
You can't control who applies, what skills they have and who is eventually appointed so you need to focus on putting in the best possible application you can.
Its a school admin/office based job that is spread over 5 days. The finish time is 4.30pm so for anyone with young children that would possibly mean arranging afterschool club or childcare. And for 2-3hrs work per day it probably wont be financially worthwhile for some people. It may also deter people from travelling any distance as it would hardly cover their petrol if being paid minimum wage approx.
What do you think? I'm going to apply and I'm hoping I get an interview. So far Ive applied for 10 school admin based jobs but not even got to interview stage but these were for 27+ hrs per week.