If your children are 9 & up, this might work. I just returned from a 5 day trip with 14 girls -- each had $50 in spending money (most on a VISA debit card). They almost didn't buy anything! They were very picky about what they bought, weren't asking the parents that accompanied them to buy this or that & if they did, we just told them it was their decision how to spend their money (and they needed to carry their own purchases). Amazing how much less they wanted things when they had to be 100% responsible for them!

