Earning cash in 1970s England

[boltonia]

What would a boy living in an underpriviledged area of England do to earn some spending cash in the 70s?

I'm not thinking about getting an actual job like a paper route. I'm more interested in less scheduled things, like redeeming coke bottles and such. What would an 8-12 year old boy with the freedom to run the streets do?

Thanks!