Hassan told BuzzFeed News he usually tries to take videos when something interesting happens in his class, like when his students learn something new, so he can share it with their parents later on.
He said he initially shared the video to his Instagram stories, but it somehow made its way to Twitter, where it went viral.
After that, he decided to tweet the video himself to answer some of the questions he was receiving about special education and Maisarah, the girl in the blue scarf who has global developmental delay.