When it came to teaching our kids about “stuff,” we kept it simple. When our children turned 12, they were on their own. (Not really, but it sounds more dramatic that way.)
In reality, that’s when our children became responsible for budgeting their own money. Usually when kids get an allowance, they view it as “fun money.” We wanted our children to learn that responsible financial stewardship means you give first to God, then put some away for savings, use another portion for responsibilities, and then you can spend on fun stuff.