Farm apples, sell your product for a currency (stones) at a loss, use stones to extend your business and your trading range, make refined products out of your apple, sell them for a higher price, reinvest in gold mines etc.
I came here to improve my daughter understanding of math, we ended up discussing how to grow a business.
Only one bad note: a gambling mini game at the end gives you a boost of in game money, not a very good idea for a game that teaches about business making...
gratifying ending music, my daughter goes back to the game just for it!