From experience.
Two boys I'd seen in the area a few times and had played football with once, asked if I had any jobs for them to do. I said no. The following week they asked again. I said no again. (There was no strategic reason for me saying no I feel I should point out).
The following week they asked again and I thought that they could perhaps do something I was meaning to do myself, namely watering the plants in the front and back of the house and also sweep up the dead leaves and put them in the bin. The boys (who are brothers) were about 6-8 years old and so the prospect of earning 50p each for half an hour's work got them excited.
They were keen to impress and did a good job. Afterwards, I gave them their wages as well as some extra sweets and told them to come back next week to work again.
A few days later I could hear a bunch of kids being raucous in the alleyway at the back of the house. I noticed the two boys that swept my leaves amongst them but at that point they hadn't yet seen me. Then a girl within the group inexplicably grabbed my recycling bin and pushed it over, spilling the contents on the ground. I shouted over "What are you doing?!" One of the boys that had swept up for me answered that the girl (who probably about 7) had been in a bad mood all day and so she must have just lashed out with rage at my bin.
I remember thinking at the time that this was a particularly sensitive explanation for a kid no older than 8 and so I told him to help her pick up the bin then. He repeated the reason why the girl knocked over the bin and I said "OK. That's fine. You can all help her put the bin back and get all the recycling back in there"
So that was it. Myself and other adults in the area began to find jobs for the local kids to do, and because they appreciated having nice little jobs, and would hate for their friends to jeopardize it for them, this came to have a positive impact on the neighbourhood. People are more friendly to each other as kids parents get to know the adults their children are doing small jobs for. Connections are made, local intelligence (who is who and what they do etc) is increased as well as an improved sense of community.