Last time I started a post on teaching financial responsibility to your children. One very important aspect of financial responsibility is creating a budget. Don't be afraid to show your child your family's budget. Explain to your child how you keep track of expenses. Teaching children to fit expenses into earnings can be difficult, but practice will help. For example, next time you're eating at a restaurant, tell your child, "You have XX amount of money to spend at the restaurant today. What you pick to eat has to stay within that budget."
Another great way to teach budgeting is to go shopping together. This will allow your child the opportunity to learn the value of things and relative prices. Ask your child why he/she thinks one loaf of bread costs more than the other. Ask them if the extra money is worth it. You can further involve your child by helping him/her clip coupons. It's a great way to teach your kids one way to save money.
One additional note on financial responsibility is to remember to keep having these conversations and to make sure the conversations grow as your child grows. Talk to your teenagers about credit cards, interest rates, mortgages, etc. Before you know it, credit card companies will start sending information to your teen. Make sure you've had enough conversations before that time so they can make responsible financial choices when they are on their own.