The #1 thing you can do to save money when you have kids

Unless you live off grid without the influence of media, your children are likely to have favorite characters that steer their wants and needs. Be it Disney's Frozen, Star Wars or Cars, there are endless products emblazoned with these characters.

You can easily spend thousands of dollars indulging these purchases, because what's cuter than a $299 Cars bed or even this $3,999 Millennium Falcon version? Add in the bedding, pillows, posters, backpacks, lighting, wastebaskets, rugs and artwork, and you've invested a ton of money in this theme.

Instead I recommend that you choose attractive but neutral stuff for your kids that will outlast each new whim. You can certainly add in a few accessories to complement their current interest. Pillows, posters and a couple of stuffed animals won't set you back much, plus they're much easier to change out when your kids' interests naturally evolve.

I spoke to one mom who chose a neutral high-quality backpack for her kindergarten age son, and then added a "Herbie the Love Bug" patch for customization. As his interests expanded, she would pick out the stitches and sew on a new one, and by fifth grade her son's five-year-old backpack featured a "Beatles" patch.

"I doubt he would have wanted to carry a Cars themed backpack as an eleven year old, and I doubt a character backpack would have held up anyway," she told me.

One tip is to only buy character items that a child would naturally grows out of, like T-shirts, pajamas and shoes. So go right ahead and buy that Frozen T-shirt for your four year old, but forgo the coordinating comforter, lamp and iPhone case that's sure to embarrass your daughter come middle school.

Because what happens when your child hits puberty and ages out of their former obsession, and their formerly adored rooms are suddenly deemed as "babyish"? You've spent a bundle crafting a theme to their each and every possession that is now more embarrassing than dad's incessant knock-knock jokes. But worry not, as there are a number of solutions.

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Donate to your favorite charity

Whether you're a fan of Goodwill, Salvation Army or a local non-profit, you can always donate outgrown stuff for a tax deduction. This Salvation Army value guide clarifies the amount you can legally deduct from your taxes, so make sure to write a detailed list of every donated item for a maximum deduction.

Sell on eBay or Craigslist

Selling on eBay and Craigslist has never been easier, especially now that most of us have a camera and Internet access built into our mobile devices. Create good pictures, take measurements and accurately describe each item and you might be able to get at least get some of your money back.

Give it the slip

Slip that Princess or Star Wars comforter into a duvet cover like one of these inexpensive Ikea versions. That's what I did when my now 18-year-old son outgrew his love for Teletubbies, and to further bring down the price, I even picked it up at my local Goodwill.

The great cover up

Decoupage over childish themes using Mod-Podge. Here's a Miss Spider's Tea Party wastebasket which I updated by covering with vintage maps. This transformation not only got my son through his teen year wastebasket needs, but it also accompanied him to college. (This may seem inconsequential, but recent studies suggest that the average college student is spending $899.18 to outfit their dorm rooms. Add that on top of room, board and tuition, and suddenly that wastebasket from home sounds like a great idea!)

Conclusion

By choosing to not spend excessively on stuff that needs to be repurchased every few years, you're able to keep your money available for the things that really matter. Although it's tempting to indulge your kids' every whim, you lead by example when you teach that possessions are not disposable, and that smart people spend wisely. This singular choice will save you hundreds, possibly thousands of dollars throughout your son or daughter's childhood. Now, if we could only figure out a way to update dad's knock-knock jokes!  

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