Kids on farms still do it, just that things are more mechanised now.

I used to drive a tractor and trailer on the road at harvest time, when I was 13 years old, perfectly legally.

My boy started working on Saturdays when he was 16, and on til he left school with his A levels at 18. He was also working evenings at Dominos Pizza by then though.

Both of my Filipino stepkids had jobs as soon as they could legally work (paper rounds at 13, I think it was...then working in shops).