I would be very wary of a secondary school that at present has no IT technician. You may be walking into a giant mess. However any experience is good experience. See if they have an old server that is mothballed in a cupboard somewhere. Get it out and put Server 2008 R2 on it, break it, fix it, break it some more. Just experiment as much as possible, but not on your live environment. All is good for your CV.