The only fact you have is that 12% of primary school teachers are male. Thats it. Nothing else.
I cant think of anything that can be done to improve it because (like you) I do not know the reason for the low figure. If its because men are being turned down, then theres a problem. If its because they just do not want to do the job and would rather teach older kids, then there is not a problem. We don't know which it is.
I dont give a stuff about women being under represented in any job. I have already said this with your parliament argument
I think as long as someone does a job properly, it doesn't matter what genitalia they have.