“The Science of Well-Being”
Coursera (English) ~ 19 hrs, 3/week

Wildly popular class at Yale on happiness, well-being and other elements of positive psychology - including exercises, daily habit-changing and integration into real life

“Young people and their mental health”
Class-Central/Future Learn (English/Dutch) ~5 hrs, 2/week

Similar class from University of Cambridge/Groningen but maybe addressing a bit younger audience than ours - might be helpful nonetheless

“Positive Psychiatry and Mental Health”
University of Sydney (English) ~ 21 hrs, 5/week