The problem isn't really the average salary. It is the newly qualified teachers on a starting salary of around 20K and a massive student loan who have a problem. They soon see that their friends with similar qualifications earn a lot more so they are lured away from the prefession into other careers. Few new entrants last beyond the second or third year. As those of us with 30+ years experience but who are too knackered to continue call it a day there will be even more problems.