Newest update: My daughter is now 6.5, and I still think this is one of the best things I've bought on Amazon.  We recently saw one of those horrible ASPCA commercials, and she asked if we could send money to the "dogs in cages."  She's got the money, so she gets to make those choices.  I love that about this system.  She has donated money to the WWF twice.  If I were to do it all over again, I think I would just commit to $3 per week ($1 per container) - I didn't think that would add up fast enough, but $2 per week has added up way faster than it needs to, and so she doesn't fully understand scarcity.  Even so, she has a much better understanding of money than she would otherwise, and basically has for as long as she can remember because we started this when she was just 4.  Her little sister is 2.5, I'll be buying another one of these when the younger one turns 4.  I don't think there's anything special about the bank itself (by the way, it has held up perfectly - I was afraid the rubber band would lose its elasticity over time, but it still holds the pieces together strongly), but the system is solid, and one of the aspects of parenting that I actually feel like I'm doing right.