I expect that to pay very little. Games and little apps like that make money from advertisement. It's obvious that only a percentage of their income will be allotted for the rewards of the players and it's obvious that it's not going to pay that much because you really didn't do anything but open their app, and click some stuffs. Faucets are very much like that and they pay

Personally, I wouldn't teach my kids how to earn bitcoins. I would teach them about bitcoin every now and then but not to the point that I'm trying to make them money on their own. Money should be provided by the parent and it's in the law. Your kids truly want to make money by themselves and spend it on things because at that stage, they are very materialistic. I wouldn't let them do that, they will be missing out on childhood and one day they will look back thinking how they spent their time making money instead of enjoying life itself while they are still young.