Wellspring Academies formerly known as Academy of the Sierras (or AOS for short) is a therapeutic year-round boarding school, and the world's first behavior modification facility exclusively for overweight and obese teenagers. It was founded by Ryan Craig, who also served as its first Executive Director.
The program calls itself for "the best short-term results ever reported for a weight loss program" 
As of February 2007, AOS has two facilities.
- The California campus is locate on 42675 Road 44, Reedley, California, about 30 minutes southeast of Fresno, and has 90 students ages 13-18 .
- A second campus, located on Lambs Creek Road, Brevard, North Carolina and known as Academy of the Sierras North Carolina (or AOSNC), has roughly 20 students ages 11-16 .
- A third facility will open someplace in the state of New York in June 2008.
AOS is operated by Healthy Living Academies, a division of Aspen Education Group. It is closely affiliated with Wellspring Camps.
The reference to "the Sierras" has been criticized, as most Westerners refer to the Sierra Nevada mountain range area as "the Sierra", singular. AOS maintains that "Sierras", plural, is appropriate because the Spanish translation of Sierra is "saw", literally translating into Academy of the Saws.
The diet has been criticized , but such a very-low-fat diet is supported by rather old investigations by the World Health Organization  and the American Diabetes Association . A number of articles in Washington post disclosed that the diet, which only contains one quater of the fat recommended by Weight Watchers could risk causing an increased risk of gallbladder problems .
A number of experts - among them Anjali Jain, a pediatrician at Children's National Medical Center question the expense and necessity of boarding school. They point out that there is no longterm study of the results gained after graduation .
One of the not so positive case is the one of Jahcobie Cosom, who ended up weighing 562 pounds .
If the teenagers do not work the program or violate simple rules like having a cell phone in the facility, they can be transported to a wilderness environment called Sierra Adventure Program (SAP), which is seen as the facility's equivalent of solitary confinement. At the California facility it is located on an island in the Kings River .
If a teenager experiences homesickness, the parents are given some trick to manipulate the child to stay in the program. 
In the news
Unlike the programs in the other categories, Treatment centres in the Weight loss Division do not allow client to arrive by the use of a Teen escort company. At least they state so on their homepage . Instead the parents ask for a series of phonecalls from staff, which should persuade the student to attend the programs. However, a participant on a Dr. Phil show was sent there by the use of a Teen escort company .
- "Fixing Generation XXL", by Kate Fillion, Macleans, 2006-07-19
- California facility on Google maps
- The area around the North Carolina campus
- Extreme Low-Fat Farm Abusing Obese Kids, Jimmi Moore
- Alice H. Lichtenstein, DSc; Linda Van Horn, PhD, RD; ; for the Nutrition Committee,Very Low Fat Diets, American Heart Association, Inc. 1998
- Dietary fat and diabetes, Diabetes Care 2002
- One Day at a Time, Scenes From a Recent Visit to Wellspring Academy of the Carolinas, By Sandra G. Boodman, The Washington Post, May 20 2008
- 'Fat School' - In the Hills of North Carolina, a Controversial Experiment in Weight Loss, By Sandra G. Boodman, Washington Post Staff Writer May 20 2008
- When 'Fat School' Failed Him, , By Sandra G. Boodman, Washington Post Staff Writer May 20 2008
- Sacramento Bee Special Report, See chapther 3
- What happens if, after a month or two, my child decides she doesn’t want to continue, and wants to come home?, program homepage
- What if my child isn’t interested in attending AOS?, Program homepage FAQ
- The Dr. Phil House: Teen Intervention, Part 3
- Survivor group: CWS and AOS Alumni, Myspace
- Survivor group: Academy of the Sierras Alumni, Myspace
- Survivor group: Academy of the Sierras, Myspace