High school is a very stressful time for any teen. Whether they are having trouble trying to fit in or to get an assignment in on time its puts a lot on a person shoulders. Here's a list of activities to help relieve stress for those struggling to survive in high school or just in life.
PSA: FINALS ARE STRESSFUL AND THIS CAN HELP!!
Listen to calming music
Slow-paced and instrumental music can induce relaxation by helping lower blood pressure and heart rate, as well as decreasing the levels of stress hormones.
https://psychcentral.com/lib/the-power-of-music-to-reduce-stress/
Exercise
Exercise and other physical activity produce endorphins which are chemicals in the brain that act as natural painkillers which calms the body.
https://adaa.org/understanding-anxiety/related-illnesses/other-related-conditions/stress/physical-activity-reduces-st
Spend time with loved ones
Being around loved ones often gives people a sense of safety which results in the chance of becoming stressed in that environment unlikely.
Laugh
When people say laughter is the best medicine they aren't kidding, it relaxes the entire human body, by boosting the immune system, triggering the release of endorphins, protecting the heart, and by burning calories.
https://www.helpguide.org/articles/mental-health/laughter-is-the-best-medicine.htm
Keep Your Mind Occupied
Activities such as reading, drawing, and even cleaning can stimulate the brain and inheritably keep the mind off stressful ideas.
Use a Stress Ball
It prompts you to squeeze and release, which can leave you feeling less tense than you started.
https://www.huffingtonpost.com/2013/04/09/stress-relief-tools-old-fashioned-remedies_n_3022241.html
Whenever someone is stressed it is best for them to keep their mind occupied in any way the possibly can. Try a few things on this list and see what works for you.