"I want to run a business I believe in," he says. "I'm pretty passionate about schools and education. I like the idea of trying to create an ethos that encourages people to learn and develop their talents."
Wesson, 34, is one of several people from outside education who have signed up for the NPQH.
He taught at a school on the Isle of Wight after completing a law degree at Cambridge and a one-year teacher's training course, but soon developed strong views about forging links between companies and schools. After four years in the classroom he was offered a job at the London headquarters of the engineering and construction giant Costain, responsible for developing its community relations policy.
Six years later he had shot up the promotion ladder to take the top personnel slot, responsible for 10,000 employees in a company with a #163;1 billion-a-year turnover.
With a wife, two brothers and a sister who teach, as well as his own previous experience, Wesson is familiar with the ups and downs of life at the chalk face. But he does not want to return to the ranks, preferring to use his management experience to go in at the top.
He sees the NPQH as a way of increasing his credibility when, in two or three years, he starts applying for headships.
The NPQH, part of the Government's strategy to raise standards in schools and give heads a more professional image, is also being promoted as a way of attracting people like Wesson into schools. But he dismisses the idea that schools are somehow backward and need to catch up with the commercial world. "Industry can learn a hell of a lot from education," he says.
"Schools and teachers are underrated. There's no better training for management than running a class of 30 children, yet that is not recognised."
Nick Nelson, head of Queen's School in Bushey, Hertfordshire, would agree. The only difference between running a school and any other organisation, he says, is that a school is generally far more demanding.
Nelson is a history graduate who went on to become managing director of the delivery firm DHL and then to run the Post Office's parcels business, with a staff of 12,000.
At the age of 45, when many in his position are starting to think about a generous retirement package followed by lucrative consultancy work, he decided to give up the executive lifestyle and train as a teacher.
He did a PGCE and took a job at Queen's School. Three years later the head left and the governors wanted to replace her with someone who had sufficient management experience to meet the demands of running a 1,300-pupil grant-maintai ned school. Nelson got the job.
"A business is run for the customer, and everyone in the organisation understands that," he says. "But in a school you've got so many different customers. There are the children, the parents and the governing body. There is the local community, the Government. The list goes on. One of the interesting parts of this job is balancing all the different constituents."
Did taking on the head's role prove difficult for someone with only three years' experience in the classroom?
"It's the most challenging job I've ever had," Nelson says. "When you're in industry you have all sorts of specialists who can advise you if there are any problems. In a school, everyone is busy because they've all got teaching to do.
"I had to learn very quickly about some of the nuts and bolts issues like timetabling and curriculum planning. But whether you're running a business or a school, the issue at stake is what you are trying to deliver and what quality standards you're trying to achieve.
"It's about establishing management systems which enable you to motivate people in the organisation to work towards those aims, and monitoring to see if you have made improvements."
Nelson admits that some formal training would have helped him when he took on a headship. He is encouraging his staff to sign up for the NPQH, but sees potential problems with the time it will take when most aspiring heads are already working all hours.
The practical orientation of the course is right, he says - before taking on his present position he spent time visiting other heads to learn the best ways of doing things - but the bureaucracy involved in signing up for it seems burdensome. The whole scheme must be reviewed very quickly, perhaps after six months, he says, to see if take-up and drop-out rates suggest it should be streamlined.
Wesson is also aware that the NPQH is a new qualification and some crucial issues appear not to have been sorted out yet - for example, how people like him who are not based in a school will deal with the very school-based curriculum.
But he is looking forward to joining the ranks of those who, like Nelson, have swapped highly-paid executive roles for teaching. And despite having spent years in the hard-headed world of industry, there is still a good deal of idealism involved. "I enjoy the leadership and management aspects of running a business," he says. "Becoming a headteacher would be a way of using those skills for the benefit of individuals and society as a whole."