These girls took what they loved and turned it into big business. Seventeen money coach Farnoosh Torabi says you can too!

Name: Amanda, 17, New York, NY

Business: EcoDog Treats, ecodogtreats.com

Her Passion: Animals

Earnings: $750 a year

Her Story: Amanda was devastated when her dog, Princess, died from cancer in 2006. So she combined her biggest loves--animals and the environment--and created vegetarian dog snacks. She figured that healthier nonmeat dog treats could help pets live longer--and would spare the lives of other animals too. "It took losing Princess for me to actually do something about what I love, instead of just thinking about it."

Name: Kalissa, 17, Peoria, IL

Business: Kalissa's Cakes

Her Passion: Baking

Earnings: $250-$300 a month

Her Story: Kalissa always loved baking when she was bored. When she was living in Texas, tons of her friends started having quinceaneras (birthdays for 15-year-old Latina girls)--and she realized there was big cake money to be made. So she started her own quinceanera cake business. Then after her family moved to Illinois, Kalissa came up with a business plan to fit her new town: "It's like Build-A-Bear meets cakes--people can decorate cakes together and have fun."

Name: Marci, 17, Asheville, NC

Business: MarciG, marcig.etsy.com

Her Passion: Crafts

Earnings: $680 a month

Her Story: Marci had been making pottery since she was a little kid. But it was actually bad luck that set her on the path to success: Last summer, she didn't get any of the jobs she'd applied for--so she decided to turn her hobby into a business and launched an online pottery store. She customizes her signature pieces for shoppers, and now more than 40 percent of her clients are repeat customers!

GET STARTED! Want to launch an empire from your bedroom? Check out these sites for insider tips on how to do it:

1. sba.gov/teens

2. college-startup.com

3. mindyourownbiz.org

4. entrepreneur.com/tsu

Source: Seventeen Magazine; author: Farnoosh Torabi; seventeen.com