It seems if you're a parent and your young child is buying candy wholesale and selling it, your and their future may be pretty bright.
My father's friend had a wholesaler's license (or whatever it is you need). I got her to buy me snacks/candy/soda from some big wholesaler. I sold it at the local pool/lake out of a cooler for much lower prices than the snack bar.
I had a number of similar "businesses" like this over the years, culminating in a much more successful web design business when I was 14-15.
I also did door-to-door sales of custom imprinted holiday cards. I got into that game be sending in a flyer from a comic book. So basically for me, my method of getting into entrepreneurship revolved around comic books.
I understand society enforces the law differently on kids than on adults - and I definitely did this when I was a kid myself - but isn't it a little strange that the first lesson kids seem to get in entrepreneurship is how to create markets in the intersection of things kids are allowed to do and parents aren't allowed to do?
Lots of other things I did sell though: fruit from the garden, some kind of world wildlife foundation stamps on the train (train passengers are a captive audience!) etc.
Ticket scalper once when I was a teenager (I invested basically all my money in buying 6 tickets).
It all seems like just right place right time stuff. Who wouldn't sell their candy if there are buyers at a good price?!
For what it is worth I have been in variations of (successful) self-employment for practically all my career; but I am not much of a sales person.
For extra quaintness, when I was 11 and change, I had a yard sale and sold a lot of my stuffed animals and all of my My Little Ponies (for $80) so I could buy a faster computer. :)