Often when they went grocery shopping, 6-year-old Matt would beg his mom to buy something. Kari was tired of negotiating with Matt and explaining why she wouldn't be buying what he wanted. She decided she needed a new approach to their shopping trips.
Before she went shopping the next time, she sat down and wrote a list of everything she planned to buy. When they got to the store, she gave the list to Matt along with the duty to check things off as they put them in the cart.
When Matt wanted something her to buy something not on the list, she'd ask him to check if it was on the list. If he couldn't find it on the list, then they weren't buying it today. To Kari's amazement, Matt offered to help make a better list next time but he stopped begging her for things not on the list!