Participants that meet study criteria based on the clinical information obtained at the first study visit will be invited to begin a course of Cognitive Behavior Therapy (CBT), an empirically validated talk therapy commonly used to treat children with anxiety. Children will receive individual treatment using the Brief Coping Cat Manual. The Coping Cat program (Kendall 1994) is an empirically supported child-focused CBT treatment for children with anxiety disorders. Throughout the program, children are encouraged to practice techniques learned during therapy sessions through homework or "Show-That-I-Can" (STIC) tasks. Parents attend weekly check-ins and two parent-only sessions. STIC tasks will consist of specific SmartCAT modules in the smartphone app as assigned at the end of each session. Participants might be asked to interact with other children and adolescents or study staff as well as leave the therapy building. This is to allow participants to become more comfortable in situations that make them feel anxious by gradually exposing them to the specific situation. Parents are not treated as co-clients, but are considered consultants to the child's treatment and are asked to provide some collaboration and assistance in exposure planning and homework.