Source: Social Security Administration.

For a full-time employee, the average workweek can be nightmarishly long. Based on a Gallup survey of full-time U.S. adult workers from its 2013 and 2014 work and education polls, just 8% claimed they worked less than 40 hours per week, while 42% said they worked right around 40 hours per week. This means half of all respondents work more than 40 hours in a typical week, with nearly one-in-five working 60-plus hours. 

No wonder Americans treasure their down time. Statistics from the U.S. Census Bureau show that the average American spends between five and six hours per day on leisure and sports activities, with this figure not surprisingly higher on the weekends. But here's the real surprise that some Americans may not be aware of: There are quite a few hobbies that make money.

11 hobbies that make money
If you're looking to put some extra cash in your pocket, and you have a passion for particular hobbies, then the following hobbies could make you some serious money.

1. Garage sale maven
Have you ever driven by a garage sale and wondered if there were possible uncovered treasures for sale? If so, you're not alone. Based on data from Signs.com, there were 165,000 yard sales held each week across the U.S. in 2013, with an average of 690,000 people buying an item. Annual revenue generated from these yard sales is in the neighborhood of $220 million! But the real money is made by the item buyer. Reselling yard sale items on eBay produced an average premium of 462% over what the buyer paid for the item at the yard sale.


Source: Flickr user StockMonkeys.com.

2. Couponing
I admit it, I've shaken my head at friends that spend hours each week cutting coupons. However, the reality is that taking the time to scour the weekly coupons can be a serious money-saving venture. According to Ilovecouponmonth.com, about 80% of consumers used coupons while shopping in 2012, up from just 64% in 2007. Furthermore, some 2.9 billion (yes, with a "b") coupons were redeemed in 2012, adding up to approximately $800 million in discounts for consumers. The site estimates that if every coupon distributed were used, consumers would each have saved over $1,500 in 2012. Yet the actual savings proved to be about $11 per person based on coupons redeemed.

Source: Flickr user R. Polllard.

3. Professional gaming
Yes, millennials, your inner urge to veg on the couch and play video games the entire weekend is a hobby that could make you money. Now, here's the catch: You're unlikely to be a gaming professional at multiple games or succeed if you only devote a few hours here and there to gameplay. The key to success is devoting yourself to a single game, practicing a lot, and potentially building a team of experienced gamers around you. This way you can enter professional gaming tournaments, coach new players on how to dominate a game, or even stream your gameplay in order to generate money.

4. Writing/blogging
I can attest firsthand that writing and blogging as a hobby can turn into extra cash. I began my adventure with The Motley Fool as one of its bloggers in 2009, rising up to become a Foolish contributor shortly thereafter. My success is just one example of how writing for fun, whether it be a blog or a full-length book, can make you money. Being a freelancer, self-publishing a book, or using your blogs or writing examples to land a job as a journalist or paid website blogger could be your key to extra cash.

Source: Flickr user Shubert Ciencia.

5. Craft-making
Among the hobbies that make money, craft-making might be one, if not the, easiest to monetize. From knitting sweaters to crafting ornate centerpieces, the market for unique arts and crafts spans all 50 states. Prior to the Internet, it had been difficult for crafting hobbyists to find a market for their goods. Nowadays this isn't an issue. In addition to marketplaces such as eBay and Amazon.com, services like Etsy provide a platform for handmade and vintage goods to be bought and sold.

6. Music teacher
Do you secretly dream of reliving your days of being in a high school band or forming a band out of your garage? There's a solution that could allow you to express you love for music and make some extra cash in the process. Becoming a music tutor or teacher, be it for the piano, guitar, drums, or any other instrument, can allow you to focus on your hobby while sharing your love for the craft with others of all talent levels. Best of all, you don't have to be Slash on the guitar to be a guitar teacher. Many people seeking tutoring are beginners, and if you've been playing an instrument for a few years you likely have the knowledge needed to help them along.


Source: Flickr user thetaxhaven.

7. The stock market
You may not think of investing in the stock market as a hobby -- in fact, some of you might consider saving for retirement some of the most laborious work you'll do in your lifetime -- but for some people (like myself) it's an extremely satisfying hobby. Researching companies, gaining knowledge of the intricacies of how businesses interact with one another, and understanding the competitive nature of businesses and products can actually be quite enlightening. Plus, if you do follow the stock market, you probably realize that over the long term it tends to rise by about 8% per year. It's plausible the stock market could be the most profitable of all hobbies.

Source: Flickr user MarieLinden4.

8. Photography
If I had a dollar for every time I saw someone list photography as a hobby or "like" on social media I might be rivaling Donald Trump's bank account. OK, perhaps that's a bit of a stretch, but overall Americans really love taking pictures. Admittedly, not everyone that takes photos has the knack to be a professional photographer. Then again, not every consumer can afford the services of a professional photographer, and a professional photographer can't always catch the perfect photo. By turning to social media sites like Flickr (in order to sell photos that are in demand), or promoting your services at a discount to professional photographers, you could turn your love for photography into a money-making business.

9. Pet sitting and walking
If you enjoy being around animals or have what resembles a barn in your home (again, I can attest with two cats and a dog), then consider pet sitting or walking dogs in the neighborhood as a hobby that could make money. Dog walkers earn an average of $15 to $25 per hour, and your hobby could actually translate into a part-time business. Plus, you'll be able to surround yourself with all of the different breeds and personalities that domesticated cats, dogs, and other animals can bring to the table.

Source: author.

10. Refereeing or umpiring
Do you love sports but no longer have the stamina or 20-something body needed to keep up? There's a simple solution: consider becoming a sports referee or umpire. This way you get to be around the game you love, and you'll be paid for your time.

In my late teens, I worked as a basketball referee during the summer (I was an avid basketball fan at the time), while my father has been a baseball umpire for more than a decade now, earning paid trips to Cooperstown, the home of baseball, once a year. Speaking from experience, the money earned from refereeing or umpiring can be a nice income boost.

11. Personal shopping
The last, but certainly not least, among hobbies that make money could be the most fun of them all: shopping to earn cash! If fashion is your forte, you could consider becoming the personal shopper of someone who simply doesn't have the time of day (or fashion sense) to pick out the right outfit. According to PayScale.com, a personal shopper might start out at $15 or $20 per hour as a beginner, but could wind up netting 10% to 15% of the total purchase in income, depending on their experience level. Imagine that folks: getting paid to shop!

Next time you have some free time and begin "nerding out" with your favorite hobby, consider how it could wind up putting extra cash in your pocket.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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