Jezi you must do what you feel is right. do you mean by the risk factor involved in doing a primary education degree is that you will be stuck in teaching forever if you do it and won't be able to change careers later? Or that you really like French and would have to give this up? I can give you my experience if it is any help.
I had to make a similar decision, always loved history but wanted to be a primary school teacher. Anyway my career advisor advised doing a history degree then a PGCE which I did. A decision I have never regreted. However I will say that a PGCE is extremely intensive and very hard work. You do not have as much knowledge to begin with as someone who has completed a teaching degree for 4 years, but it shows you are up to a certain standard. You are always learning in teaching all the time anyway and you get very well supported in the first year of your job which you have to pass to attain qualified status. There is nothing like learning on the job. Friends say they are glad they did the 4 year course as they felt more prepared but if you are willing to work hard you soon catch up. At the end of the day you have got to have a way with children to be successful. Alternatively you could apply for a placement in a school for a year and learn on the job, (this is once you have a degree,) we have a student in school at the moment doing this not sure how it works, but I could find out if you want me to.
As far as doing a French degree I don't think there would be a problem getting on a PGCE course especially as they now teach French in primary schools, although you can check this with individual universities.
It is up to you whether to go away to university or stay at home. There are pros and cons to both, I went away and loved my time at uni. However there are major financial worries these days that you do not have so much more of if you live at home. Or do they do the course you want to do at your local university? Mine did'nt. Anyway keep your options open for now and talk it over with your parents, friends and teachers. Hope this has been of some help I will stop rambling now. One thing I can definately say is I have been teaching for around 8 years now and enjoy it tremendously, it is hard work but the rewards are great!

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