Realistically, so many things are contributing to society's obesity and other health issues.
School games/sports only really work for the sporty/team kids - they put off those who are less fit or who don't like team sports. Most games teachers are the team sports lovers/bullies of 20 years ago, so the problem just perpetuates from generation to generation. We need a whole new attitude to exercise in schools, concentrating more on alternatives such as gym work, yoga, "solo" sports/exercise, so that the less "sporty" ones who can't do well in team games can do other things. I hated sports at school and ended up pretty inactive, but in later life, I've done all kinds of "non team" sports, such as golf, swimming, squash, tennis, skiing, cycling, walking, etc and found I was actually pretty good at them and enjoyed them.
School cookery is a shambles. When I was at school 40 years ago, it was all bakery, i.e. scones, cakes, etc. When my son was at school 10 years ago, it was all curries, vegetarian/vegan, etc. One extreme to the other. How about teaching basics/fundamentals such as how to make a roast dinner, how to cook a chicken, how to make a lasagne/cottage pie, etc?
NHS dietary advice is pathetic. I have diabetes and have had "consultations" with several NHS dieticians and diabetic nurse specialists. None have given me any workable/sensible eating options. All their advice is "eat more lentils", or "have fruit and nuts for breakfast" - basic text book "advice" more or less just regurgitating what their guidance books say. But absolutely zero practical advice! For someone with no interest in lentils or nuts for breakfast, I need someone with more realistic advice. In the real world, due to caring and work commitments, I'm going to eat something from a packet in the morning, and probably an evening meal including something from a tin. When I've said this and asked for advice as to which kind of breakfast packet cereal is best, or which tinned soup is best, they can't answer - they just go back to their "lentils and nuts" speech. Yes, I know whatever Kelloggs packet I have at breakfast time isn't perfect, but in reality, it's what I'm going to have, so I'd like to know which would be best to minimise diabetic issues. They can't answer because they don't know. I've had to work it out for myself by trial and error, checking my blood sugar levels after each type, likewise with tinned food. The NHS "specialists" aren't in the real world, and that's why the "healthy eating" message isn't working - they're just parroting the "perfect world" options rather than real life/practical options which would help!