Schools have the opportunity to teach skills such as CPR and more general first aid training as part of Personal, Social, Health and Economic (PSHE) education. Currently, it is up to individual schools precisely what to teach in PSHE, and they are encouraged to work with expert organisations to teach such skills.
However, at this point, I’m not convinced that legislating for first aid training to be a requirement in the national curriculum is the right approach. The national curriculum creates a minimum expectation for the school programme. Quite deliberately, it does not represent everything that a school should teach. Rather it is a framework around which schools can construct a programme which works best for them. In addition, schools do not have a monopoly on the provision of education to children, as parents and voluntary groups outside school also play an important role.