We have recently started to give our 5 year old an allowance. When we did, we wanted to teach him about tithing and saving (he already knows spending). My wife, Cindy, wrote a post about our system for teaching D3 these important concepts. You should check it out. It’s working great!
Update: This post was so popular, that I wrote an article about teaching children how to tithe. Feel free to check it out, too!