Primary age children are great at picking up new languages when they get masses of input. The younger, the better. Primary schools cannot provide this.
Research shows that direct instruction of primary age children does not lead to great progress. e.g. Gaelic in Ireland.
Some academics say any language learning at primary is good because it lengthens the overall exposure time to a foreign language.
Compulsory languages at KS2 is an exciting opportunity, but don't forget that the large majority of schools were doing it anyway up to 2010, and with some training and funding.
Best hope: raise awareness in pupils of language and culture differences. Give a smattering of knowledge and experience. Create interest and enthusiasm for the future. Open minds.
Primary schools, in general, do not have the time and expertise to do this really well. Research showed that by 2010 coverage was patchy across the country. It always will be.
Primary languages can enhance other skills: literacy, listening, speaking, self-confidence.
Continuity with secondary schooling almost impossible to achieve - too many feeder schools, different languages, too many different teachers involved.
Danger that poorly taught languages at primary school will put pupils off. It happens.
Scandalous that there is minimal financial support for this from government.
Teachers can only grasp the nettle and be positive, share best practice and support each other. But we have to be realistic.