A few weeks before my daughter Emma's most recent birthday -- her ninth -- she was sitting at the table leafing through supermarket ads.

"Mom, eggs are on sale. We could have scrambled eggs for breakfast at my slumber party. Oh, wait, another store has waffles on sale. That might be easier."

I smiled to myself. My long quest to teach my kids about budgeting had finally paid off.

The high cost of celebrating birthdays had first become a topic of discussion in our house four years earlier. Our youngest at the time, Daniel, now age 5, didn't yet have strong opinions on the subject, but Emma and her brother Jacob, now 8, longed to imitate their friends' expensive gatherings.

They wanted it all: elaborate store-bought cakes, pizza, and entertainment. Or they asked to invite all their classmates to a laser-tag party or something equally pricey. When my husband, Barry, and I tried to suggest less expensive options, we'd hear, "But my friend had her birthday at the zoo and invited the whole class!"

Barry and I felt torn. Of course, we wanted our kids to enjoy and remember their birthday parties. But we also had to keep the cost within our means.

Then Emma's next birthday loomed on the horizon. She really wanted a store-bought Barbie cake (with a real doll in the middle!). It would cost $40 and serve just eight people. I tried to explain how extravagant this was when you really thought about it, especially since we'd need to buy another cake to have enough for everyone. She looked at me and said, "But it's my birthday. How come I don't get to decide what to spend money on?"

She had a point. Suddenly, an idea occurred to me: why not just set a party budget and let the birthday boy or girl decide how to use it?

I shared my brainstorm with Emma and Jacob. Starting with Emma's birthday, we'd be instituting a new policy. The kids could plan their own parties -- as long as the total cost of each shindig came to less than $100.

Of course, this sounded like a lot of money to my kids. Emma eagerly announced that she wanted to invite her class to a swim party at her grandparents' pool. We figured that around 15 kids would attend, plus seven relatives and family friends.

Emma wrote down her wish list for the party, and with a little research, we were able to estimate the cost of each item:

"That's it," Emma proclaimed proudly. "I told you it wouldn't be that expensive." We added it up together. The grand total: $201. Emma was very surprised to see that she was $101 over budget.

"Let's take another look at the list," I suggested. What, I asked, was most important to her? She really wanted the Barbie cake, but she decided that we could supplement it with homemade cupcakes for $3 instead of buying a second cake.

Then she crossed the pinata and the pizza off the list. The guests would be so busy swimming, they probably wouldn't even miss either of them. We found some art sets on clearance for a dollar each to go in the goodie bags. By working together, we were able to bring the total down to under $100.

The party was a great success, and so was the idea of sticking to a budget. Once they were required to toe the bottom line, Emma and Jacob became savvy shoppers. I no longer had to be the meanie who said, "No, you can't have the $70 cake shaped like a train." I could simply point out that buying that cake would leave just $30 for all of their other party goodies, and they would quickly rethink their plans.

My children have come to enjoy working within their birthday budgets. It gives them more control over the planning of their parties and helps them to decide what's truly important. Jacob and Daniel have even combined their parties some years to maximize their dollars (see the box below). I'm now looking forward to the day when our newest arrival, 2-year-old Samuel, has enough birthdays behind him to start planning his own parties -- and learning to budget for them too.

PARTY PLANNING POINTERS
The author shares some tips for helping birthday budgeters get the most for their dollar.

1. Shop at a dollar store, where price comparisons are simple. Kids can decide whether to buy three packs of eight "character" cups or one pack of 50 plain cups.

2. If siblings want to have a combined party (our two older boys have birthdays three weeks apart and some of the same friends), they get a budget of $150.

3. Invest in a fun cake mold. I bought a car-shaped one that can be decorated for a boy or girl, and it makes my kids feel that they're getting a special cake.