Optical illusions can be fun. This coin eating piggy bank with a frog sitting in it is a pleasure to watch. Kids will love it so much, you will be out of change. Place a coin in it and see how the frog swallows the coin.
 

 
Like magic, coins dropped in appear to vanish without a trace. Nevertheless, attempts to punish the greedy animal will prove futile. Perfect for forming a saving habit in your children, driven by an unstoppable urge to feed the frog.
 
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