This is one of my favourite Buddhist stories.
It is a Zen Buddhist story. Zen Buddhism is the type of Buddhism that is common in Japan. Zen was brought to China by the Indian monk Bodhidharma about 600 years after Buddha's death. It then spread to Korea and Japan, and also became very popular in the West from the mid 20th century.
The main ideas of Zen Buddhism are the same as all Buddhism. These are impermanence (= everything comes and goes, nothing stays the same), non-attachment (= being free from desire), non-self (= acting selflessly), and mindfulness (= not thinking, but experiencing life).
Watch the video about the two monks, Tanzan and Ekido, as many times as you like until you understand the dhamma message.
When you think you understand the message, write a short answer in the test sheet, beginning "I think the message of the story is that we should ...