No, definitely apply. I'm a senior leader in a school and if you have most of the qualities in the person spec, go for it.
Applications for admin jobs last time we recruited (part time, school hours) were in the main, terrible and had less than 10! We recruited from outside of education so the person didn't have SIMS experience.
I read somewhere that men are very likely to apply for a job when they meet most but not all of the spec but women almost never apply unless they can tick every single box. So I say do it and definitely apply! If it’s a school job then they are often quite competitive but you never know. Worst case scenario is you don’t hear back.
You can definitely learn how to use sims and if you have experience using other database software explain your it literate and confident you would be able to pick it up quickly. Our office staff have been working there for 20+ years and some of them only know very basic features. I wouldn't let it stop you!
I went for a temp job that desired Sage experience. The agency put me forward as I had other skills/experience. Fast forward a few months, I easily picked up the sage knowledge I needed and they have asked me to become permenant!
Schools can be odd over this. If it's a standard primary school office job and you're reasonably competent with a computer you'll learn everything you need to know about SIMS in an afternoon and yet (often because the leadership don't understand it) schools ask for SIMS experience like it's a big deal.
If you'll be responsible for producing performance data in a secondary, it's a bit more complex.
IME school admin jobs get 100s of applicants so the shortlisting can be very harsh just to whittle it down to a manageable number. That said, no-one who doesn't already work in a school will have the required experience so unless it's better paid than other comparable jobs in the area, why would those with the experience apply unless they're desperate to get away from their current job? (a warning sign IMO).
So, I'd do an excellent application detailing all the ways you do meet the criteria, any work or volunteering you have done with children, demonstrate an understanding of safeguarding (Google) and details of all the software systems you have used and how quickly you've picked them up, but most of all get your application checked and double checked for spelling and grammatical errors.
Often when faced with 100s of applications, the smallest error can result in the no pile, simply because you have to use something to differentiate between all the "OK" applications. Also, you'd be amazed just how poor lots of applications are. Make sure yours isn't one of them.
Oh yes and absolutely do visit. Again schools are odd like this, when else do you get the opportunity to visit before application? But lots of schools won't consider shortlisting someone who hasn't taken the time to visit. They want to believe you want to work at their school, not that you're looking for any job that fits in with your DC. Go well briefed on any special circumstances or recent achievements for their school.
I understand school jobs are in demand but I'm not necessarily looking for a job that fits in with DC, I already have that. It's more I'm looking for something that doesn't hire me rigid like my current job where I'm on my own most of the time. (I thought I'd like that but it's so lonely!)
I applied for the job but didn't get an interview.
Which is probably as well as I was on salary calculator today and the monthly take home was nearly £1k less than my current salary as am on more hours and about £3 an hour higher rate. I had decided to worry about that if offered the job. It's moot now!
The only thing I don't have is Sims and experience in a school which I will never have if I never get a job in one.