https://www.youtube.com/watch?v=_w50TfdCmKU (exercise)
https://www.youtube.com/playlist?list=PL4eGobYp7-J_lcEJIKvzubSOr5LrvTj2I (videos of old time activities)
https://silveractivities.com/digital#/page/all(mental activity)
https://www.youtube.com/watch?v=1Z_VH-uGKIM(exercises in chinese)