Money Maze, in exchange for honest review from Tomoson.
The first time, I used it, I put in a little change and it was easy to solve. It helped the ball was already on the right side. The next attempt, I put more money in and tried to solve it. took me a few weeks to get it solved again. My oldest also tried to open it with a fork, but failed. This is a great mind activity challenge/piggy bank for kids
You can purchase a money maze, using the link above. The money maze is prime eligible