If I recall correctly, my parents sent us to school with PB&J, or baloney and cheese, on white bread. Add a piece of fruit and a zip lock of chips or cookies. We bought a carton of milk at lunch. Not one of my eight siblings was even pudgy. At home, we at mac-n-cheese, mashed potatoes, veggies grown in the garden, meatloaf, spaghetti, and lots of other pretty common menu items for large families. So what's the difference between then and now?
First, PE was mandatory in school. When we had recess, we played, ran, played ball, climbed the monkey bars, etc. When we came home from school, we had chores, including tending the garden and livestock. Nobody got paid for doing these things, it was expected that we contributed to family upkeep. When we had leisure time, we were put outside to play. We explored the woods, build forts, went for long hikes, chased fireflies and trapped frogs and snakes. We were not permitted to sit in front of the TV and computer shit hadn't been invented yet. I imagine my parents wouldn't have allowed us to spend too much time playing computer games, either. My parents actually came out and played with us, soccer, softball, riding bicycles and hiking, among other activities.
But then, my Mother stayed home and raised the children. My Dad worked two, sometimes three, jobs to make ends meet. You could also bring home a month's worth of groceries for $150-$200. I guess we really haven't improved all that much, considering the social problems we have now...
Oh, well, thanks for letting a geezer maunder about how horrible it was before we had all this great technology...