I think they do this every Monday morning. Nice way to start the day.

Update: “Raijo Taisou”
A description from our school:
This year, to experience a Japanese tradition, we’ll have Raijo Taisou time. We’ll do it once a month usually the first Monday of the Month at Upper and Lower Yards in the morning at 9:25am. Raijo Taisou is a traditional Japanese stretching exercise with music. It’s about 5 minutes long. This month’s session took place on Mon, Sept 13. Please join us in the yards. Please check out this Raijo Taisou movie on youtube. Thank you to JBBP Volunteers for sharing this tradition with Second Community Program! It was such fun participating in this physical activity and starting off the day on the right foot!