Hi, having seen lots of messages from student teachers about how difficult the PGCE is I would have to say are you sure that you will be able to handle both subjects as well as doing your PGCE? It's an intensive course!
I'm hoping this would make me more employable and with the demand for Maths teacher so high, maybe even help my pay. I have completed Maths up tyo A Level and would interested in Key Stage 3 and Maths.
It is not possible to train for two such different subject areas at the same time. A PGCE is a very intense course and trying to combine two such different disciplines would be impossible in my view. There are some joint PGCE programmes and some courses do require a knowledge and understanding of different disciplines (e.g. science where there is an expectation that you teach all the sciences to the age of 14 and, ideally, offer two sciences to GCSE level. Even then, you would only offer one science to A level). I am aware of maths/physics PGCE programmes and maths/IT, but nowhere does history and Maths. One thing you may want to consider is doing a mathematics enhancement programme which is a six month fully funded course designed to take those with some maths (As/A level) and provide them with the subject knowledge to teach maths to GCSE and/or A level. While on the course you also are provided with a £200 per week tax free bursary. The good news is that once you have QTS it is not restricted to your subject (or even your age range). Once in a job, if you can persuade a head that you can teach another subject (history) then you could learn that 'on the job'. As you know, maths teachers are in short supply, more so than history teachers so I would seriously consider training as a maths teacher and offering history as a second subject rather than the other way around (in addition the PGCE bursary for maths teachers is much higher - £9,000). The Enhancement and bursaries are OK at present, but with the new coalition government, who knows how long they will last.
Having just completed a History PGCE myself, I wouldn't lie and say it has been an easy year. History and Maths are so different that I think that trying to learn and practise the different pedagogies at the same time would probably be extremely difficult! I suggest the same as what other posters here have said - if you think teaching Maths is a better career option then you should opt for teaching Maths instead (the competition for places are slightly less than say for a non-compulsory subject like History, and you also get more money).