Children aged -15 years are never suitable for gambling because it can damage their behavior later in life.
It depends on their mindset. At the age of 15, I doubt they will have an interest on doing gambling.
But if they really did, more on it was because of their curiosity. I'm sure at that age they already know the difference between what's the good thing to do and not. If we try to force and convince them to ignore gambling the more they want to know about it.
It would be a surprise to you that children of this generation starts gambling activities from primary school,where they engage in playing PS2 games and bet on it.From that stage,they graduate to playing bets,since they already have the idea.If a particular child loves gambling,it doesn't matter the age,they can be 12,and will start gambling from that age till they grow big.
Yeah, I agree with @Lordhermes as I watch some kids playing PS2 games and gamble with their friends.
I am not sure how they gamble but they use money doing that, as I heard some of them ask about the payment.
If their parents always tell them about the risk of playing gambling, I am sure they will be aware and try to stay away from gambling and not be involved in the games even if their friends ask them to join or watch.
With the growing technology nowadays, the children become smarter because they can do something that sometimes their parents do not know.
It needs more attention from the parents to guard their children's. Otherwise, it will be difficult to tell them when it is too late.