The Anxiety and Depression Association of America (ADAA) works to prevent, treat, and cure anxiety disorders and depression.
Anxiety overview and an article from Psychology Today on building resiliency: 
This helpful, student-friendly, Anxiety ToolBox is a workbook developed by CalPoly and includes information, strategies, and worksheets to assist with thinking through anxiety issues. From their Emotional WellBeing site: "Anxiety Toolbox focuses on helping you understand anxiety symptoms and build skills to manage these symptoms. The modules cover: (1) understanding anxiety, (2) introducing a method for slowing down and disentangling the experience of anxiety, and (3) developing alternative responses to anxiety. "
Also from CalPoly, this workbook on Recogniti
on, Insight, Openness (RIO) focuses on building skills and creating flexibility in how you respond to distress. The sessions include modules dedicated to: (1) helping you gain a deeper understanding of your concerns, (2) creating flexibility in how you view and approach these issues, and (3) helping you take steps toward living with a wide range of emotions. By the end of the workshop, you will have a better sense of your personal values and how you want to focus your energy.
Also from CalPoly's Emotional WellBeing site, the Seeking Serenity workbook is" informed by dialectical behavior therapy and is designed for students who experience overwhelming emotions that feel difficult to manage. The sessions include modules dedicated to: (1) distress tolerance, (2) emotion regulation, and (3) mindfulness. By the end of the workshop, you will have strategies for better managing overwhelming emotions.
