Why would you want to give such a potent weapon of you teaching the class to the administration? They could easily edit it to incriminate you. And, what you might consider a little joke or humor might be viewed as an insult to a kid, with all the cultural differences you encounter in a NYC classroom. A Hispanic male teacher in the Bronx recently was fined a huge amount for using a word of Spanish slang. Seems it means one thing in one country and another thing in other Spanish-speaking countries.
If I call on a Chinese student to answer a question, I often get the brain-dead students screaming out, “That’s racist!” Everything is racist to them. They can parrot perfectly what Al Sharpton and his ilk pollute the airways with, but couldn’t tell you what was on the board 5 minutes ago. What is racist about calling on a Chinese student? Only the brain-dead could tell you.
If there is no objective record of what happens in the room, how will those kids ever learn what is actually racism and what isn’t ? Only by reviewing an objective recording, unedited and with timestamp on each frame, can discussion happen. Otherwise it is up to each person’s recollection and interpretation through the filter of their own prejudices.
On the Chinese question, it probably has to do with some implied slight that you called on them because you expect them to be smarter than the non-asians and didn’t give the non-asians a chance.