This is an idea for one of those programs where they set up small industry in poorer regions to help break the poverty cycle in either government initiatives or charitable organisations.
If you set up a small tin smelt (like a blacksmiths) with all the moulds for a bicycle, you could get the local youth to gather up tin cans or aluminium cans in exchange for a bicycle, made from the gathered tin. They could gather enough for there own bike, as well as enough for another bike, so the recycling business can sell that one for profit. The person can do that as much as (s)he wants, giving or selling the ones they make spare. There could also where they get a certain amount of cash for their cans if they don't want a bike, have a bike and want to keep gathering. Also, buying back their second bike etc. could be a way to do it. That way the furnace can afford fuel for the smelting, and also maintaining the equipment. They could also make other things as well, of course. Such as helmets. Or jewellery.
Of course, you could also teach smelting and blacksmithing for the extra keen. It would probably break even, but its the brownie points of feel goods that are the profits here.