I've got an 11 year old local kid that helps me out in the shop once or twice a week. He loves the work I give him and the skills he's learning will give him such a big head start when he eventually gets old enough to get a job. He's polite to customers, understands instructions and rarely asks for help unless a bolt is too tight for him or the job requires 2 pairs of hands.
He already unpacks my deliveries and checks the quantities against invoices, then calculates markup and prices items.

I can't find a 16 year old that can (or is willing) to do what he does. He's going to be a very successful bloke in the future and I'm lucky to have him around at the moment.