Not sure why you were told to sign up for the educational program, except it's a good deal. On the screen at the checkout is where you play to get the gold coins (if you're lucky enough).
Check the flyers too. Sometimes they make special offers to earn a gold coin.
At the end of your transaction before you pay, make sure that you play the game on the screen (for Payment at Big Y) and play to try to win gold coins. That's how I try to earn them.
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