According to Dave Ramsey, God refers to money and stewardship more than 800 times in the Bible. How do we impart Godly wisdom regarding money to our kids?
When my oldest was about seven years old, we read through The ABC's of Handling Money God's Way by Howard and Bev Dayton of Crown Ministries and then began giving him an allowance. This curriculum is meant to be a 12 week study geared to children ages 5-7. However, I am currently doing it with my nine-year-old, and it is working well. You can read and discuss a chapter in ten to fifteen minutes, and the course has a teacher's guide which you can purchase separately.
The book starts with the idea that the Bible is God's word, and He has something to say about money. It then moves on to 1 Chronicles 29:11: "Everything in the heavens and earth is yours, O Lord." The book then discusses stewardship, hard work, tithing, saving, contentment, spending, debt, wise counsel and obedience to parents, honesty, salvation, giving to the poor, and friendship. All this is woven into story form. Elizabeth and her friends want a way to earn money for a puppy, and they turn to her mother for help. Mrs. Day replies, "God loves you. He wants to help you use money in the best way. We will have twelve lessons. In each lesson you will answer some questions. And we will learn a Bible verse" (Dayton 6).
Personally, I suggest doing no more than two lessons per week, consistently going back and revisiting themes and giving the ideas time to "soak" in. For example, it is very counter-cultural to view everything we "own" as really belonging to God. While you're at it, examine yourself. We cannot teach our children to be content, stay out of debt, tithe, or save if we do not do these things ourselves. Personally, I was convicted about how I see things as "mine" because I worked hard or saved up for them.
Rather than the "jar" system that is presented in the book, we set up an "envelope" system. After finishing the book with my then-seven-year-old, we decorated envelopes and started him on a massive allowance of $1.00 per week. For us, the allowance is a tool that we use to train our children in financial stewardship, and for a seven-year-old, $1.00 is easy to break down into percentages: 10% tithes, 20% savings, 10% giving, and 60% spending. I would recommend an amount that would not make saving for things they want "too easy" to achieve. Now at age 12, his break down is: 30% Me, Myself, and I, 10% tithes, 25% pets, 20% bank, and 15% giving, and when he receives money for birthdays or other occasions, he divides up his money as he desires into his categories with tithes being mandatory. As a side note, we do not give any compensation for chores.
The Daytons have written another book for older children called The Secret of Handling Money God's Way for ages 8-12. However, after doing The ABC's of Handling Money God's Way, my oldest latched onto the principles, and we have not needed the second book. At some point, we'll need a stewardship course that delves deeper into the world of credit cards, debit cards, checkbooks, budgeting, etc. -- and when we get there, I'll share it with you.