Not sure where you got that from!
I work in a school (which is part of a group of Academies) and the school employs its own network manager and technicians to look after the network and associated infrastructure. This is an entirely typical setup, at least in my part of the SE of England.
The only schools which have outsourced IT around here are those who were forced to by the abortion that was BSF - a terrible scheme which involved people running school infrastructure who had no idea of how it works in real life. (Trying to make teachers phone to lodge a support call for a whiteboard not connecting to a PC, for example, whereas in real life they send a pupil into the IT office, someone goes to the class, sorts the issue in a minute or two and the job's done). Needless to say that as soon as they could, schools that were BSF'd for IT went back to the traditional, on-site support method. Heck, some BSF schools even broke out of Northgate and RM's control whilst they were still contracted to use them, figuring that the penalty fees were worth paying to regain control for themselves.
We used to use RM, but they were very overpriced for what you received. Just buying Lenovo or HP machines saved around £100 per machine straight off. We moved to a "vanilla" Windows 2008 network, ditching the expensive and somewhat lobotomised RM Community Connect software, which saved even more money - we no longer have to pay a tax on every PC, instead our licensing is managed on a "number of full-time staff" basis. That gives access to Windows, Office, SCCM and we can upgrade as and when we want to, rather than waiting for RM to come up with a custom package.
Good riddance to RM, in my view. They were far too expensive for what they offered.