Instilling values

In an age where "lets get the better and bigger thing" is rampart, how does a parent instill values and principles in the minds and hearts of their children. That the next toy car or a new doll will not make them any happier in the long run. That "small" can be beautiful. That "humility" can be endearing. That being a child in their childhood is okay and that there is no need to act and talk like an adult before their time.
It makes me loose hope at times. But I am learning to take one step at a time. To respond to a hello with a hello. To remember to thank the birthday girl/boys's mom after enjoying the party she invited you to. To wait patiently till his birthday for that new wonderful toy he is been waiting for. And finding that the wait made the gift all the more wonderful.