Happy Birthday to me! Why are we spending so much on kids' parties?

Elaborate cakes costing hundreds of dollars. Backyard transformations that include water slides, bounce houses and stages for musicians, magicians or a fairy-tale princess. Special venues. Professional planners to orchestrate the tiniest detail.

These days, it's common for parents to spend hundreds of dollars (or more) on venues, entertainers, dessert tables and party games. Children's birthday parties have come a long way in the past few decades. And so has the cost.

Experts say several factors are fueling the trend —most notably lack of time and an increased demand for convenience.

"A lot of the parents really want to take off the stress of hosting a birthday party themselves," said Jessica Langlois, marketing manager for AZ Airtime, a Scottsdale trampoline park that hosts about 115 birthday parties each month. "It just makes it easier on everyone, and the kids always have a good time."

AZ Airtime's birthday parties are primarily for kids 2 to 14. Packages range from about $145 to upwards of $500, depending on the number of kids and add-ons, such as extra food and goody bags for guests.

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The dedicated party hosts at the venue "will serve the cake, serve the pizza, set up and clean up," Langlois said. "The parents, all they have to do is sit around and have a good time."

Birthday celebration at Playtime Oasis

Another contributing factor? Pressure to match or top elaborate bashes frequently found on Pinterest boards and such websites as Hostess With the Mostess, a party-planning blog that has an entire section dedicated to children's birthday parties.

Jamila Watson, owner of a Phoenix-party planner business that caters to kid birthdays, said parents "are looking for something different, not your cookie-cutter (party). I would say half of the themes that we do are custom."

Her custom packages start at $700 and include a professional party host who conducts activities and games and facilitates the present opening, plus party favors and a keepsake gift for the birthday child.

Bottom line: If you can imagine it, you can pay someone to make it a reality. Kids' birthday parties are big business.

Big business

Data on children's party party costs are hard to find. Two major research groups that track many areas of consumer spending — the NPD Group and the National Retail Federation — don't keep statistics on birthday-party expenses.

But there is much anecdotal evidence to suggest that the kiddie-soiree market is booming.

Things to consider

• An ongoing babybenter.com poll that 26 percent, the overwhelming majority of respondents in any single price category, said they spent more than $500, with the greatest expense being the birthday cake.

• In January, two families in England made international news after getting into a Facebook fight after one mother sent the other family an invoice when their 5-year-old son failed to attend a birthday party. The party, held on a ski slope, cost the equivalent of about $25 per person

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• A Google search for "extravagant kids birthday parties" returns more than 254,000 results, including articles in magazines and blogs, and photos of celebrity and non-celebrity bashes featuring ponies, elegantly designed tablescapes and multitiered cakes that look as though they are the centerpiece at a wedding.

• Pump It Up of Tempe, a leader in the kids' birthday-party business, opened its first indoor bounce-house space 15 years ago. There are now 135 locations across the country. The firm, which is private, does not have to disclose how much it makes in annual revenue but says it has hosted more than 2.5 million birthday parties since 2000. Party packages range from $200 to $500, according to its website, and the company just announced plans to expand into Monterrey, Mexico.

In Arizona, there are literally hundreds of specialty businesses catering to the lucrative — and competitive — kids' birthday-party market. There are yoga-themed party packages, coached sports parties, puppet performance parties, craft making and dress-up birthday events.

A Scottsdale circus school offers private birthday packages, as do go-kart venues, skating arenas, rock-climbing gyms and water parks. Birthday kids age 10 or older whose parents are willing to shell out $450 can party like an astronaut on a simulated space mission with up to 32 of their closest friends.

And the new American Girl retail store in Scottsdale, which opens Saturday, Aug. 22, already is taking birthday party reservations in its bistro 90 days out. Their birthday parties range from $30 to $47 per child.

Birthday celebration at Pump It Up

Party planner Watson tapped into the trend four years ago. Her business, Parties on Purpose in Phoenix, specializes in planning and hosting often-elaborate birthdays for kids. It started as a part-time venture but now is a full-time job, with six party hosts.

Pre-set party themes, including POP Star Party and Royal Princess Adventure, start at $395 for up to six guests. They include glamour makeovers, mini "rock star" stages and even dance parties where guests learn a choreographed number.

"I would bring my daughter to parties and I would see the moms were so stressed out trying to be a host to the adults and the children," Watson said. "We de-stress the whole environment and make it fun. Parents deserve to have fun, knowing that everything is taken care of."

In addition to convenience, Watson said her clients are craving entertainment and venues that stand out in the crowded landscape of kids' birthday parties. She said she has hosted plenty one-of-a-kind parties, including a unicorn-themed princess event complete with a miniature pony wearing a unicorn horn.

Watson says she even has created a VIP lounge for parents — complete with music, mimosas and glitter tattoos — at a child's birthday party.

Childhood memories

Sandra Torre of Cave Creek is one mother who doesn't mind shelling out for her kids' birthdays. The way she sees it, there are only a few years of magic, of princesses and superheroes, when moms can go a little over-the-top and watch their child's eyes light up.

Before you know it, she said, you'll have tweens whose eyes don't light up, they roll.

"I don't feel like we get enough birthdays with our kids," Torre said. "I'm willing to spend a little bit of money on the young birthdays, because you don't have that many of them, and they're such great memories. ... I'm going to have a lot of fun planning the birthdays until I can't anymore."

Her daughter, Madeleine, just turned 5. Torre tapped into Madeleine's "Star Wars" obsession by hiring Luke Skywalker and Princess Leia impersonators, who kept her daughter and almost 20 friends' rapt attention with Jedi training, lightsaber practice, relay races, R2-D2 crafts and more at a community park.

Pizza and cupcakes followed. Previously, Torre has thrown "Sleeping Beauty" and "Frozen" — complete with grown-up princess performers — for Madeleine.

Sara Bernstein, owner of Storybook Entertainment in Scottsdale, was Torre's go-to call for the "Star Wars" theme. Bernstein has a background in youth theater and hires young actors and performers to host birthday parties in character. Her most basic package, a character meet and greet, costs $80 for 30 minutes and includes a storytime or song, singing of happy birthday and photos with the birthday child and guests.

But Bernstein's superheroes and princesses don't just perform, they often will lead up to a dozen kids through at least an hour of organized games, crafts and activities, starting at $150.

"I have 24 characters now," said Bernstein, who started her business just 16 months ago. She credits such things as the popularity of Anna and Elsa from Disney's "Frozen," photos on Pinterest and more-involved parenting for taking birthdays way beyond cake, punch and simple games.

"It's a different world than when we were kids," said Bernstein, a Scottsdale mother of two sons. "The parents come to parties just as much as the kids do."

Competitive market

The birthday business, has, in fact, has gotten so competitive that some juggernaut venues are trying to expand their revenue stream.

Pump It Up, for example, is offering more open jump hours and special events, such as "parents night out" evenings, said Wendy Krone, its marketing communications manager.

As a working mom, Krone said she understands why birthdays are a huge niche market.

"At the end of the day, I'm just going to go somewhere" that can host a birthday party, Krone said. "We try to make it a stress-free experience for moms. We take pictures, we cut the cake, we coordinate the food ... we handle all the decorations."

Elizabeth Blutstein, a Scottsdale mother of three, has spent a lot time both attending and throwing birthday parties for her kids, ages 5, 7 and 9. They have been to bowling parties, painting parties, dress-up parties, skating, bounce-house parties and a puppet-theater party.

Blutstein has done the at-home party too, including a sleepover for her 7-year-old daughter and a magic-themed party for her 5-year-old son, complete with a magician.

This summer, she threw a birthday party for Charlie, 9, and about a dozen friends at the AZ Airtime trampoline park. With his energetic friends, she said it only made sense to get out of the house.

"It was really good," Blutstein said. "You basically walk in and two hours later you walk out and your house is perfectly (clean), the way you left it … I think having 12 boys running around your house, that's a little much."

Torre, who tracked down a Princess Leia for her daughter's fifth birthday a few months ago, has no regrets about giving Madeleine a dream birthday. It has paid back in spades — and good memories.

"It was such a great party. She still talks about it," Torre said. "She still uses her Jedi lessons. ... She'll tell some random stranger that she had a 'Star Wars' birthday party."

Now, it's almost time to start thinking big for her son, who's 20 months old.

"No big parties for him yet," she said, "but I can't wait for him to have his turn!"

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