As I mentioned, this is Language Security 101. The earlier you start speaking French, the more confident you will be later. Yes, we must provide opportunities to speak French at a very early age, but later as well. French must not be just spoken at school.
Even if children begin to speak French at a very early age, after grade 10, they will wonder how they can live in French in a minority situation when they have never spoken French anywhere but in school. We have to start teaching them very young to trust in the quality of their French, but they must have opportunities to speak it in places other than school. That allows them to see that they can speak French everywhere in order to break down that minority complex.
That is what I experienced too. People should be able to speak French in places other than school so that they realize that they can actually speak it, without people judging them because of their accent or the mistakes they make, and so that they see that their French belongs to them, and that is fine.
You only improve your French by practising it. We often believe that people’s French will be improved if we are constantly correcting them. Actually, I think it is the opposite. By not correcting them, and by giving them opportunities to practice, they will improve quickly. Knowing that we say “une mère” not “un mère” comes only with practice.