What are symptoms of scoliosis in teenagers?

Usually none- Sometimes one will note that a shoulder or hip area is higher than the other or the chest looks different. That is if the curve is of sufficient size or rotated. Otherwise, there are no symptoms with a typical idiopathic scoliosis unless severe and then it could affect lung and heart function. If there are symptoms, then look for a cause other than scoliosis & that may also be causing the curve.
Can be subtle. In many cases, the findings on a patient with even a large scoliosis curve can be subtle. This is in part why schools will screen for scoliosis. The most common findings are an asymmetry in the hips and pelvis, an elevation of one shoulder, and a rib hump, otherwise known as an asymmetric trunk rotation. Most adolescents have no symptoms at all unless they have really large curves. Thank you.
None usually. In children and teens, scoliosis typically does not cause symptoms and is not obvious until the curve of the spine becomes moderate or severe.
Curve of the spine. Scoliosis is often asymptomatic. Generally the first sign of scoliosis is a curvature or asymmetry of the spine which is easiest to see on forward bending. Most teens do not complain of pain. More severe scoliosis may cause shortness of breath, low endurance or other signs of the internal organs being compressed by the spine.