Time preference is a big component in life success. There's not a lot of practical ways to discuss this with a small child, so "save up for the bigger/better toy" is what you get. If you have better ways to teach this lesson to your kids, I highly recommend doing it.
As an adult, 'wait a year' is quite reasonable, but kids live in dog years, when i was a kid 'wait a month' felt like i have to wait untill i grow old and get reincarnated
Start with shorter time horizons. Do your kids earn an allowance? Pay them interest. Every dollar they still have at the end of the week, give them a dime. Be creative.
