I'm an IT Manager with over 15 years experience and there is something I've heard many times - the best technicians don't always make the best managers. That is because being a good IT manager requires a lot of compromising between the needs of IT and the needs of the business, and that's something techies don't always appreciate. I know in many schools the IT Manager is usually a technical manager who is expected to look after the servers and system on a day-to-day basis - a sort of senior senior IT technician, if you will. But as IT has become more crucial to operations in schools (as with any and every other business), they are slowly coming round to the understanding that they need more than just a good techie at the helm. So I'd say it's not just about getting the right qualifications, though these are important for your CV, but having the right mindset - being able to shift focus from the technical details to the bigger corporate picture: understanding the needs of the business and delivering relevant projects on time and within budget, being good at managing, motivating and developing your staff, good oral and written presentation skills, handling admin and paperwork, etc. I many instances, the job can be MORE about these skills and less about the technical stuff, although you will always need an understanding of IT systems. That is probably why a lot of IT managers I know in various industries didn't even do an IT or engineering degree, but developed their IT skills along the way.
Many technicians assume the next upwards move in their career is to become an IT Manager, but the technical and the managerial are actually very different paths. If you're a very technical-minded person, the next move is probably to develop your skills along a specialist path - security, networks, etc. Depending on the field, you can earn much more than some IT managers. But you'd probably have to leave the education sector for that!