Advertising pitched to children is often heartbreaking in its effectiveness. Just ask a parent.

The advertising vortex is especially pernicious during the holidays, sucking your children in and creating desires for things they don’t need and, in some cases, are worse than junk.

Parents can fight back by planning for the holidays well in advance, drafting a budget with your kids – and sticking to it.

“For children over seven, state the family’s holiday budget and divide it equally among the kids,” says Karen Waldron, Ph.D., author of Unleashing Kids’ Potential: What Parents, Grandparents, and Teachers Need to Know. “Ask your children what they’d like for holiday gifts and discuss it. If a teenager wants something expensive like an iPod, make it clear that it may be the only present this year. If a child asks for something that’s too expensive, say the gift is possible only if the child wants to chip in some money.”

Being upfront with children about the holiday budget helps teach them the value of money and an important lesson many adults never learn: You can’t have everything. If your kids understand this basic point, you can bet they’ll be saying the same thing when they have kids of their own.

But there won’t be immediate miracles. Many kids will use the tried (and strangely effective) tactic of whining, “Oh, Mom!” or “Oh, Dad” followed by what they think is a killer argument: “But everybody has one.”

Counter this unproductive jibber-jabber by reminding your child that they’re not “everybody” and in any case “everybody” doesn’t have a vote in your house. Then be resolute.

Waldron recommends the “broken record” tactic in dealing with repeated requests from your kids for a budget-busting gift: Say over and over and over again that it’s too expensive and therefore the answer is no. Before long, you child will answer his own question by saying, “I know, I know – it’s too expensive!” and will drop the subject... eventually.

The next step to financial maturity is teaching your child to set priorities. If your kid understands there’s a limit to holiday spending, this forces the child to decide what’s important – and that’s your opening to impart one of life’s key lessons.

Help your child define the issue by asking questions. Establish the cost, benefits and downside of each option. Start with the basics and then develop the fine points. Would your child rather have one expensive gift or several less costly items? Will the expensive gift hold your child’s interest or is it simply this year’s hot item that will fade quickly? Is it something your child will grow into or does its shelf life extend about a week beyond the holiday advertising campaign?

Defining the issues and discussing them with your child is the easy part. For some parents, the tough step is letting your child make a poor decision. If you’ve defined the issue accurately, the next step in life’s lesson is letting your child live with a bad decision. Some kids quickly realize they’ve made a mistake and say “You were right,” but a few will blame you for not steering them away from a poor choice.

As a parent, you’ve got to say: “Tough toenails, kiddo. It was your decision.”

If your child is unhappy with a poor choice, you’ve got to let them live with their decision. This isn’t punishment and it will underscore a basic point: Decisions have consequences. In the future, your child will diligently weigh the choices before making a decision and probably get it right.

Living with a bad decision is another lesson many adults never learned. Many adults think that’s why credit cards were invented – and have crushing debt to prove it.

“Some parents hate the holidays,” says Waldron, a professor emeritus of education at Trinity University in San Antonio. “They complain about the pressure in front of the kids and rush through the stores, grabbing something. What kind of a model is that for kids – that giving is a pain in the butt?”

Avoid this trap by keeping an eye out for special gifts and oddball items throughout the year. If you see the perfect thing for a relative during summer vacation, buy it and tuck it away. Be sure to discuss this with your kids. It will show that you delight in giving special things to special people and that you plan ahead.

Don’t let your children fall victim to what many have called “affluenza” – the disease of craving and overspending on junk. With a little planning and discipline, you can teach your children the joy of giving and that will make the holidays more special than anything advertisers can throw at them.