Children or teens with generalized anxiety disorder often worry a lot about future events, past behaviors, social acceptance, and school performance.

Rituals and obsessive thoughts are a normal part of a teen's development. An adolescent with OCD has obsessive thoughts that are unwanted and related to fears.

Anxiety can help focus and sharpen performance. For some athletes, however, the pressure of performing well takes its toll in the form of performance anxiety, which causes them to do less than their best.

Common phobias include fear of animals, blood, heights, closed spaces, or flying. In teens, the fear must last at least six months to be considered a phobia.

A serious accident such as a car wreck, or a natural disaster such as a flood can cause PTSD in a child. Physical or sexual abuse and neglect can be other causes.